Of course there are! In Pathfinder, there are rules for growing and developing your relationships with the NPCs of your (GM's) choice! We can take the complex, subtle and nuanced interaction of human hearts and apply the time-honored technique of making numbers go up.
The relationship rules were originally invented for the Jade Regent adventure path and were originally printed in the player's guide for it along with some information on the key NPCs who were further fleshed out in the adventure path modules themselves. Taking more than a little inspiration from recent Bioware RPGs such as Dragon Age II, the rules let you build a relationship with the NPCs as you level and at a high enough relationship (31+) you can gain a Devotion boon whose mechanical benefit represents you looking out for one another or learning something from your friendship. With a higher score you could even opt to turn it into a romantic relationship. Without further ado about nothing, let's meet our lucky bachelor(ettes)!
Sandru Vhiski, a former adventurer who used his earnings to become the owner of a trade caravan
Koya Mvashti, a long-lived fortune-teller who raised Sandru after he lost his family, who still harbors a desire to travel and see the world.
Shalelu Andosana, an elven ranger and wilderness expert who originally appeared in the Rise of the Runelords adventure path
Ameiko Kaijitsu, another Rise of the Runelords alum, a former adventurer who now owns a tavern. Also the last living heir of an ancient Minkai Imperial Dynasty in the far east, whose quest to reclaim that throne serves as the driving force of the adventure path. Based on a former PC of Paizo Creative Director James Jacobs.
If your players should notice that one of these options is considerably more powerful and important than the others then they're going to have to fight for it- the player's guide says that an NPC can only be in a romance with one PC at a time unless the DM says otherwise. Of course, it says nothing about the converse and you know what that means...
This looks like a job for THE SHELYNATOR
Shelyn: Pathfinder goddess of art, beauty, love and music.
Bards, bringers of art, beauty and charm.
Azata, a type of outsider who love freedom, emotion and many other things including art and beauty.
Aasimar: descendents of good outsiders, while the Musetouched are the music and beauty loving descendents of the Azata.
We are an azata-blooded aasimar bard who worships Shelyn. Not just any bard, but a geisha bard, because an orientalist adventure deserves an orientalist archetype. We're also a savant when it comes to performance. Our starting feat is Skill Focus: Perform because we are most art.
Our starting relationship score is based on our charisma modifier, which as a bard from a race with a charisma bonus should be somewhere between a +3 and +5. We might also have a +4 bonus to that relationship if one of our traits links our background to one of the NPCs (some of these traits work better for romancing NPCs than others). Not much happens at first level because not much can happen at first level- you can only make checks to change your relationship every time you gain a level. So we go strolling, plot happens and we're now level 2. At this point we can now court in earnest!
There are a couple of different ways to boost the relationship as you level. The most basic is to add a point to one of the scores each time you level up, but since we're playing multiball mode this isn't that helpful. The other way to boost friendships is through bribery: every time you level you can present NPCs with a single gift whose value isn't as important as the sentiment behind it, so we can find or make something nice and affordable to hand out to all of our buddies just to show them how much we care. The limiter on this is that not only do you get one shot per level per NPC, but you also have to succeed in a Diplomacy check whose difficulty is equal to your current relationship score. Since our current relationship scores are equal to our Charisma modifier at the start, and the Diplomacy check is 1d20 + our Diplomacy skill + our Charisma modifier, there's no way to fail this at level 2, or even at higher levels because we'd be increasing our Diplomacy skill and relationship score at roughly the same pace of once per level. But why settle for acceptable when you can turn up the heat? Succeeding on the Diplomacy check by 10 or more means that the relationship goes up by +2 instead of +1. You could pray to the dice gods to favor you, but if you're coming at the Empress you'd rather not miss. So let's get diplomatic.
At level 1 bards normally pick up Bardic Knowledge, which lets them add half their level (minimum 1) to Knowledge checks and make those checks untrained to ensure that a bard will probably know a little bit about anything and everything even if you invest nothing in learning about it. Nice, but the Geisha has Geisha Knowledge, which only adds that 1/2 level bonus to Knowledge (nobility) checks and adds the rest to Craft (calligraphy) checks, Diplomacy checks, and one type of Perform check chosen from act, dance, oratory, percussion, string instruments, or sing. The Diplomacy bonus is a good start but we can do one better because of the one little thing that bards get at 2nd level: Versatile Performance. Versatile Performance is a class feature that lets you substitute your skill in Perform for two other skill checks, so your skill with acting can help you disguise yourself or fast talk your way through trouble. In the Shelynator's case, one of the skills boosted by Geisha Knowledge can be Perform (Oratory), which we can also substitute for Diplomacy checks, allowing us to compare a lot of people to a summer's day! With our skill focus, racial bonus (azata-blooded are good at performances), trait bonus and class skill bonus, at level 2 we're looking at 1d20+charisma + 12 against a DC equal to our charisma modifier. We can't fail. Even if we also selected our other trait to boost one of the starting relationship scores by 4, we'd only fail on a natural 1, and if we can get a +2 bonus to our perform check from a masterwork instrument (which would be... a megaphone?) we can still make it, and even if we can't do that, we've got one other thing... spells. Tap Inner Beauty is a 1st level spell that gives us a +2 insight bonus to Charisma-based checks and also happens to be one of the signature spells of Shelyn's followers. Just light that puppy up before you hand in your gift and you're golden.
At 3rd level the Shelynator qualifies for the Deific Obedience feat to prove how much you love Shelyn. Deific Obedience lets you perform a daily ritual to show your devotion to your deity, getting minor bonuses that become much more potent at higher levels (12 and up). In Shelyn's case, it's as follows:
Inner Sea Gods posted:
Obedience: Paint a small picture, compose a short poem or song, dance a scene from a ballet, or create another work of art, whispering praise to Shelyn’s beauty and grace as you do so. The art piece need be neither large nor complex, but heartfelt and made to the best of your ability. Gift the piece of art to a stranger and pay her a sincere compliment as you do so. If there are no suitable individuals around to receive the gift, leave it in an obvious place with a note praising Shelyn and asking whoever finds it to take it with your warmest wishes. Gain a +4 sacred bonus on Craft and Perform checks.
I'm not entirely sure how you leave an interpretive dance behind for strangers to find each day, especially when book 3 of the adventure path involves you spending a better part of a year heading to Fantasy Asia by trekking across the Arctic Circle, but we are going to litter the tundra with sonnets in exchange for an even bigger bonus to our Perform checks. At level 4 we gain access to 2nd level spells, including heroism, which is an all-purpose spell that boosts your murder abilities in addition to your skill checks, plus Seducer's Eyes to better charm those who find us attractive (such as our romantic interests), and even Bestow Insight to replace our Tap Inner Beauty spell with an even bigger bonus as we level. Bestow Insight is supposed to be for humans, but aasimar with the Scion of Humanity trait also count as humans for things like feats and spells (which is both good and bad for characters, but that's a different story).
By level 6 or 7 you qualify for magic items such as bracers of the glib entertainer or the Blade of Three Fancies if you're not interested in Divine Obedience. Furthermore, as a bard you're probably first in line for items such as the Headband of Alluring Charisma to boost your various skills and abilities, and the relationship rules explicitly state that long term charisma boosts such as those from your magic headband will boost your Relationship score- so don't feel too bad about dropping 36k on a magic hat to save (or secure) your marriage! Similarly, you'll probably be boosting your Charisma score with ability points every 4 levels, and the Adventure Path ends at level 16.
Fifteen level-ups at +2 apiece will add +30 to your relationship score by the end of the module, more than enough to boost you to the "Devotion" tier of relationships and pick up a nice little mechanical trait for your time. This means that with a starting charisma score modifier of between 3 and 5, plus another 4 to 5 points of Charisma boosters from leveling and magic hats the Shelynator will have a minimum relationship score of 37, or 38 if you can get someone to craft you a +6 charisma headband instead of a +4 one. Is it good enough for love though? Let's take a look at the romance thresholds:
Koya Mvashti: 32
Shalelu Andosana: 35
Sandru Vhiski: 38
Ameiko Kaijitsu: 40
With a +6 headband you can grab any of the first three, and if you also have Childhood Crush (Ameiko) then the +4 relationship bonus will push you past the threshold for her as well. This is before you add in the dozen or more bonus points per NPC you can pick up in the adventure just by doing things the character in question likes ranging from helping others, to seeing cool locations to making friends or money or just murdering a bunch of goblins, and then there's the 15 free floating relationship points you can use from your 15 level-ups which you can use to patch up any rough spots or start the romancing a few levels early (don't invest in any one too quickly or you'll outrun your Perform check and only be getting 1 point per gift per NPC per level).
Now it's one thing to have a relationship score worthy of a romance, but it's quite another to actually start it. In order to set a course for smoochville in Jade Regent you first need to succeed in a Sense Motive check with a difficulty equal to the relationship score to find out if the object of your affection is thinking what you're thinking. This is a bit of a problem because Sense Motive is a completely different skill that uses Wisdom instead of your Charisma skill, and a DC of 30+ isn't exactly small potatoes, requiring a fair amount of bonuses from leveling, ability scores and miscellaneous bonuses in addition to just plain rolling well. It's not all bad because some of our spells such as heroism boost skill checks in general. It's also not all bad because we're still the Shelynator.
Versatile Performance lets you substitute your Perform skill for two different skills and we chose Perform (oratory) because one of those skills we can tag in for is Diplomacy... and the other is Sense Motive, thus letting us use our ridiculous bonus to steamroll our way through any opposition. Once that stage is clear all that's left is a Diplomacy check against a difficulty of 10 + the NPC's level + the NPC's Charisma modifier, and even at the end of the game it's still going to be less than their relationship thresholds. Shelynation complete, romance engaged. The only thing that will stop you at this point is if your relationship score somehow backslides below the romance threshold. That's pretty easy to avoid though, just don't be a dick because that's how things get weird.
Jade Regent doesn't just borrow the relationship meter from Dragon Age II but it also borrows the choice of paths. You can have a friendly relationship built on trust and support, or a competitive relationship built on rivalry and opposition. The type of relationship is chosen once you develop it, though it's not easy to switch paths once it's in motion. You can still boost your competitive relationship with points as you level, but while the chief source of relationship boosting for friendships is gifting, the chief source of relationship boosting for competitive relationships is insults. Instead of making a diplomacy check when you turn in your gift, you can make an Intimidate check as part of a particular insult once per level per NPC, boosting your competitive relationship by 1 or by 2 if you beat the usual DC by 10 or more. Reaching a score of 31 or higher will give you an Enmity boon where you've managed to piss each other off so hard that you learned something from it (even if it's only from watching out for retaliation). While gifts aren't supposed to cost much, insults are even cheaper and come in an abundance of forms. Just one little trick will help you reach enmity with any of the campaign NPCs- be an absolute bigot. Mock, belittle and otherwise insult their sex, race, religion, body or ability and you are guaranteed to get a response. Nobody likes a bigot.
Versatile Performance means the Shelynator can burn as easily as charm thanks to the power of musical training. The percussion option lets you use your Perform in place of Handle Animal or Intimidate for your personal insult purposes (presumably using really racist triangle solos). Pounding your way up into the 30s is as easy as pie. Your usual charisma bonuses apply, but an interesting question is raised when you run across some of the various events in the books. Giving a gift will raise a friendly relationship or lower a competitive one, while an insult will do the opposite, but what happens when you trigger any of the events in the book that raise your relationship when it's a competitive one? Since the rules for relationship bonuses offered by traits, charisma and leveling don't care if you're in a friendly or competitive relationship then it's probably arguable that other events will raise your competitive relationship as well even if it's out of a grudging respect for a person you don't personally like. The alternative is that those things become a huge waste of time and effort by undoing any progress you've made with a competitive relationship, which isn't very fun (even though your racist dick of a character probably deserves it).
Should you decide to switch gears in a relationship it gets a bit more complicated. Switching from friendly to competitive is simple: just be a total dick. Your relationship will be switched and its score will be promptly halved with no roll required as the pain of your rejection burns some bridges behind you. Making nice is harder, since it requires a Diplomacy check 10 higher than the relationship score of your current competitive relationship. So if the Shelynator has spent the entire campaign antagonizing a single NPC for +2 competitive per level (+30), boosting the relationship each level with the free point (+15), hit up all the story events that boost that relationship (+15) and has a fantastic Charisma modifier (+12) and relationship trait (+4), you could be looking a relationship score of 76 or higher if you allow for more relationship building from plot events (Ameiko in particular gets kidnapped more often than Princess Peach- rescuing her should probably count for something), another level or two (+2 insult and +1 free point per level) and even more ridiculous charisma scores from some combination of wishes/aging/succubi/vampirism/mythic, you could even crack the 80s.
How could you possibly hope to hit a DC of 90 using a completely different skill from what you used to intimidate? Well, the good news is that it's not a completely different skill- as a worshipper of Shelyn and a bard the Shelynator qualifies for Persuasive Performer, which lets you use any Perform skill in place of Diplomacy, thus increasing your versatility even further by allowing you to use your racist triangle skills to play a song of reconciliation and healing. With just the spells and items we've already acquired we're in the mid-70s for the skill check, and we can boost it further with even more feats or just by spamming bestow insight on a half dozen people and ordering them to play back-up on the tambourine (and our Deific Obedience feat also can boost our Versatile Performance skill even higher at high levels). If we really work at it we can probably hit 1d20+100 with this thing.
So after a long campaign of insults and rivalry we devote all of our strength and skill to creating the best triangle medley of reconciliation that the world has ever seen! Regardless of the roll, your song touches the heart of your rival and blasts away all enmity with its healing dingle! The power of friendship fills your hearts, halving your Relationship score in the process, but since it was in the 70s to maybe even 80 that means it's somewhere in the oddly convenient range of 35 to 40. Do you believe that love can bloom in the dungeon? Roll a Sense Motive Check and a Diplomacy check to find out!
Some of you might point out that this requires a ridiculous expenditure of resources that make it incredibly impractical for anything other than a hyper-focused character, and it's not possible to go multiball on this one since it requires the use of your free floating points from your level-up. You'd be right; this is a ridiculous waste of resources because none of this is actually needed. There's one more little rule in the romance section
Jade Regent Player's Guide posted:
Note that a PC can have a romance with an NPC with whom she has a competitive relationship—opposites do sometimes attract, after all—but this kind of romance can be more difficult to begin. If the PC’s Diplomacy check to start a romance is successful, the romance begins, and the nature of the PC’s relationship with that NPC immediately changes from competitive to friendly. This change does not necessitate reducing the Relationship Score by half in this case
You can be a toxic asshole whose relationships are defined by a steady stream of abuse and bigotry, but all of that is in the past with the power of makeouts. You can build your relationship score through intimidation, and since it uses the same Sense Motive and Diplomacy tools that the friendship track uses, all that means is that there's just one more skill you have to be good with. Of course, the Diplomacy DC is still based on 10 + level + Charisma modifier, but Ameiko is the one with the highest Charisma at 18 (with Shaelu at a whopping 8) and the NPCs tend to be lower level than you are towards the end of the game. Ameiko might still boost her Charisma score by a few points as she levels, but even she is unlikely to have a Diplomacy DC higher than the low 30s. Even a standard investment in Diplomacy is enough to have a good shot at hitting those numbers (especially with spell support), which means that the skills required for a bad romance are primarily Intimidate with a single good Sense Motive check and a decent Diplomacy check later on. The Shelynator can do this, but since there are no Versatile Performance skills that boost both Intimidate and Sense Motive you're going to need to invest in more than one performance (which isn't too bad, you get a Versatile Performance at 2nd, 6th, 10th, 14th and 18th level, and about half of your abilities support Performance checks in general). But if you're going to invest in Intimidate and Sense motive then there's one other class you can consider.
The Inquisitor. At 1st level, the Inquisitor gains the Stern Gaze feature, which adds half of your level to your Intimidate and Sense Motive skills, while being a half-orc inquisitor means you can choose a character option that also adds half your level to Intimidate checks, effectively granting you an extra point of intimidate every level (well, two points per two levels) and thus letting you keep pace with rising relationship scores. It gets even easier since the Conversion Inquisition option lets you use your Wisdom modifier instead of your Charisma modifier for Bluff, Diplomacy and Intimidate checks, which means you only need one ability score for talking purposes-Wisdom also governs your Sense Motive skill and a host of features including spellcasting and Will saves, in addition to boosting Perception (the most used skill in the game).
Of course, if you're using Wisdom as your primary ability score, your Charisma score is going to suffer for it and thus you aren't going to get those free extra 5 to 10 points of relationship score that the Shelynator gets. But low starting relationship means it's incredibly easy to meet the DCs as you level, especially since intimidate is one of the easiest skills to boost- you get a +4 to intimidate checks if you're larger than your target and ensuring that your insults hurt your rival's feelings more because your rival must now nurse a height complex. While you can pretty effortlessly get the +30 Insult boosts from 15 levels, pushing yourself over the romance threshold is going to require you to lean on the plot boosters or maybe even spend some of your precious free relationship points. You're going to be getting your groove on several levels behind the Shelynator, but at least you're getting it and building yourself a harem through the power of verbal abuse and hatefucking.
As long as we're branching out into new bold new worlds for ability scores, there's a few methods to use your Intelligence modifier instead of your Charisma modifier for Diplomacy, such as the Student of Philosophy trait or the Diabolical Negotiator feat provided you worship Asmodeus. On the downside you're going to be even further behind than an Inquisitor since not only are you lacking in the Shelynator's star power but also the Inquisitor's 1/2 level boosts and thus have to scrounge for all your bonuses the old fashion way through feats, items and spells. On the up side you can logic your way into somebody's pants.
The new investigator has a little bit of an easier time with this since there's the empiricist archetype with the ability to use your Intelligence instead of Wisdom for Sense Motive as well to help you pave the way to romance, plus you have the ability to roll an extra die and add it to some of your checks- not the greatest bonus, but at least it's something. You even share the focused scrutiny spell with the bard and inquisitor, allowing you to focus on a single target for a +5 to Diplomacy and Intimidate and +10 to Sense Motive checks. Even the wizard can have some options if you're using Intelligence for Diplomacy, since it can be boosted further by being an enchanter and having a thrush or adorable pig as your familar (and since the Thrush shares your skill points and can also talk then it can even aid your Diplomacy checks to hit on NPCs and thus redefine "wingman"). With a helping of effort you might even be able to consistently land the +2 gifts and get a sweetheart or three who loves you for your logical brain.
Should the desires of the Shelynator and friends not be slaked even by the initial buffet of NPCs, Paizo served up a second course with two more NPCs:
Kelda Oxgutter, a northern barbarian woman you rescue in the first module. You can take her back to her people, but maybe she'll decide to hang around and guard your caravan.
Ulf Gormundr, another northerner you free from prison because you need his ranger skills to help your party make the trek across the Arctic Circle without all of you horribly dying of frostbite and dysentery.
If you're looking for love, Kelda has a manageable 36 threshold, but Ulf requires a formidable 42, making him harder to love than Ameiko. It's not impossible if you're heavily invested, but you're going to start running into one of the biggest brick walls in the relationship system: time. Out of the four key components to boosting your relationship score, both your freebie points and your gift/insult opportunities are tied to you gaining a level, which means you have only a certain number of opportunities to use them- up to 15 in Jade Regent since it ends with you hitting level 16. Kelda comes in when you're level 3 or maybe even level 2 if you manage to rescue her first, so you're only a little behind on opportunities compared to the original four NPCs, but Ulf isn't picked up until the very end of the second module just as you hit level 7 or maybe even after that. Assuming you got him out early and immediately start buttering him up you've got to even farther than Ameiko with only 3/5ths the amount of time to do it (9 level-ups). Even the Shelynator is going to feel the burn- dumping nine levels of +2 gifts and freebie points will only get you to 27, requiring you to make up the rest of it somehow (unlike Ameiko, it's highly unlikely that you'll have a campaign trait that gives you a free +4 to your relationship score). Should you fall head over heels for an NPC in the 3rd (lvl 7), 4th (lvl 10) or 5th (lvl 12) module, you'll have even less time to get into the 30s and your relationship progress will rest almost entirely on a combination of having ridiculous Charisma and an absolute truckload of plot events, making it all but impossible for your average character. On the flip-side, spending more than a dozen levels in contact with the Shelynator will likely leave you enthralled by devotion and/or love (which will likely prompt you to spend even more levels in contact). You will be Shelynated, resistance is futile.
So what do you actually get from romancing everyone? Well, very little. Reaching a relationship score of 31 or higher unlocks the Devotion tier (for friendly relationships) or the Enmity tier (for competitive relationships) and grants you a different boon depending on your relationship with the NPC. For simplicity, I'm going to use D for Devotion Boon, E for Emnity Boon and RS for Relationship Score.
D: Once per session gain the benefits of her inspire courage or inspire competence performance as a swift action, lasting for RS/10 in rounds
E: +4 to saves vs. sonic and mind-affecting attacks.
D: Each session, get RS x 10 gp in free potions of your choice from Koya, and save 10% on the cost of creating potions yourself
E: +4 to saves against illusion and Sense Motive checks vs. Bluff
D: +1 dodge to AC whenever you move at least 10 feet in combat
E: +4 to Initiative
D: +1 morale bonus to saves in wilderness areas, +3 morale bonus to saves while in the forest
E: +2 to attack rolls and weapon damage rolls against a creature type chosen from the ranger's favored enemy list
D: Gain a +5 enhancement bonus to move speed once per session as a swift action, lasting RS/10 rounds
E: +4 to saves vs. fear and enhancement
D: +1 to attack rolls and weapon damage rolls for a round against any enemy who successfully attacks one of your allies
E: +2 to Initiative, Perception, Stealth and Survival checks on a terrain type chosen from the ranger's favored terrain list
None of these are keyed to romance, just normal relationship scores. For some people such as Sandru, the Enmity boon is far better than the Devotion boon (though honestly you're not supposed to know the boon beforehand), so from a pure mechanical standpoint you might want to be able to mix and match. If you don't care about romancing then a bard is better off picking a Versatile Performance like Keyboard (Diplomacy and Intimidate) to let you tailor your performance as needed, or picking up the Persuasive Performer feat to slap Diplomacy onto a Versatile Performance skill that already covers Intimidate such as the aforementioned Percussion, or possibly Versatile Performer (comedy), which covers Bluff and Intimidate.
Starting an actual romance through the Sense Motive/Diplomacy route offers no additional mechanical benefit unless you have the Childhood Crush trait. Childhood Crush normally gives you a +1 trait bonus to attacks against people that threaten your crush, but more importantly lets you make a DC 15 Charisma check once per day to get your crush to be nice to you, with a success granting a +1 trait bonus to all saves for the remainder of the day. In a game where a +1 trait bonus to a single save is already a pretty great bonus, +1 to all three is just fantastic for a trait. If you're involve in a romance with your crush you instead get that +1 trait all the time, which makes it one of the greatest traits in the game from a mechanical standpoint. Since the trait is only keyed to a single NPC (Ameiko, Sandru or Shalelu... sorry Koya fan) there's no real mechanical reason to go after more than one romance.
Past that it's just about being a bunch of nerds sitting around a table with the end game of trying to mechanically solve the question of how to get their stand-ins laid (which also describes a startling high number of Bioware romances). Going full Shelynator is just a way to embrace that role and snap up those romances before anyone else gets them.
But let's set aside talks of the Shelynator and multiballs and try to use it as the designers intended. You're a humble villager who has been nursing a crush on Ameiko since you were young and thus readily volunteer to serve as her noble protector as she fulfills her destiny! Think it's possible that a princess and a fighter like you... well, it worked for The Bodyguard, right?
AND IIII-EA-IIII WILL ALWAYS LOVE YOOOOUUUUUUU
You've got the Childhood Crush trait that connects you to Ameiko, so that's a decent start. Unfortunately, you've got no real Charisma modifier to speak of because you're a fighter, not a paladin or swashbuckler who would actually use Charisma, and your Charisma modifier is unlikely to get much better as you level.
You can throw in your freebie points as you level, but even if you hit level 20 it still wouldn't be enough for her to notice you. You're going to have to use plot events! But even if you hit every single Ameiko-related plot event in the adventure path, that's only +15, putting you to 34+your low (or even negative) charisma modifier. You're going to also need to use some gifts. Unfortunately, you run into the next problem, namely that Diplomacy is not a class skill for you. This isn't the absolute end of the world here, because all a class skill does is give you a +3 to checks using it. Then again, that's something you could kind of use given your relative lack of Charisma. But hey, we can swap Childhood Crush trait for the Best Friend trait, granting us a +2 trait bonus to Diplomacy while making it a class skill and keeping our +4 to Relationship with Ameiko. By nursing a secret crush on our best friend all of our problems are solved! Except for the part where you're a fighter and thus only get 2 + Int skill points per level, forcing you to choose between spending them on skills that prevent you from dying in battle and skills that prevent you from dying alone. But hey, love is worth any cost! Your Diplomacy skill growth could keep up with rising relationship score were you not adding points from our level or getting plot events, but a combination of those two means that you're going to eventually outstrip ourselves after ten levels or so. Still, that should be enough when combined with the free points and massive pile of plot events. You're ready for love!
Right after you succeed at a DC 40 Sense Motive check to figure out if Ameiko is interested: a skill you can't afford using an ability score you don't prioritize against a DC that would be considerable for someone who actually specialized in it. You only get one chance to succeed at this check per level and as we've already discussed you don't exactly have a whole lot of levels to make this shot. But hey, you could be a Tactician fighter, which grants you more skill points and makes several skills class skills including Diplomacy and Sense Motive, but you run into the problem of a large portion of your archetype's features ranging from crap to actively insulting the player and there's still no guarantee that you'll be able to scrounge up enough Sense Motive bonuses to be able to reliably land a DC 40+ check (since every time you increase your relationship with Ameiko beyond 40 it just makes it harder to tell if she'll love you). You can have better luck with Intimidate since it's already a class skill, but without Sense Motive you're still going to be stuck as a rival.
Piles of plot events can compensate for low charisma and Diplomacy skills in order get you into the highest relationship brackets, but even they can't get you past the gates of love. Even if you go out of your way to build your fighter as a more talky character, your quest for romance is still liable to leave you as "just friends". Some classes just aren't made to be loved.
At this point you might be thinking "so the Relationship system is a series of repetitive number grinds that heavily rewards those who optimize around it and punishes relationships involving characters who either don't invest or involve themselves in characters who show up too late. If the only equalizer in the system is having interesting story events and meaningful character interaction, why have a numerical relationship system at all?"