i'd imagine none of them because they'd all be bitter to him. at least the ones he'd partake in since there are poisons that can't be metabolized properly by the body, and the ones that can be aren't something he'd want to take more than once. the bitter ones, like hemlock, would have to be taken in small doses so he doesn't absolutely Destroy his liver, and any that taste sweet are usually a one way ticket to an early grave. besides, he doesn't need complete immunity, just enough that he won't pass away immediately, so taste is usually the last thing on his mind.

don't. practice mithridatism irl. chemicals are way more complex in reality than in fiction

ohhh the detrimental selflessness. soba has never been adverse to helping an individual- if someone asks, of course he'll help. he wants to help. he's been helping since he was a kid and he was one of the first people his younger siblings would turn to for help.

and then it twists. soba twists this idea of helping and doing good into being useful. he couldn't make it as a pirate, he's not useful in that way, but someone on the street asking him to find a lost pet or handing out flyers or thinning out beasts that stray too close to city state walls? he can be useful like that. joining an organization where the echo is paramount in defeating beings that feed off of aether and can warp the aether of other living beings? he can be useful in that way, too. if he's useful then he's needed. he's wanted. it's a nasty thought that settled in his head around the time he fought ifrit because he didn't actually know any of the scions, and none of them really knew him yet either. minfilia probably tried to talk to him, but in arr soba was a little bit more tight lipped about his thoughts and opinions when they pertained to himself.

so, in shadowbringers, with the exarch actually asking him for help in defeating the light wardens, with seeing first hand what the sin eaters entail and having the ghostly ardbert fill in gaps of his knowledge from before the flood, soba is needed on a massive scale. he's incredibly useful on a massive scale. if ryne weren't around, he would've put his foot down a little earlier, demanding answers on this secret plan no one deigned to fill him in on considering it's his life on the line and not theirs. but she is. and soba can't let her go through fighting the light wardens. not when she's less sure about her status as a person and about her desire to live than he ever was.

it's not that the scions wanted him to die, they absolutely Did Not want that to happen! at all! because he's their friend! and they're all well aware of what they've asked him to do in shadowbringers, but they didn't have time to think of a different way, and soba decided that he's going to see defeating the light wardens through to the end. because he was asked to. because he was needed. because he was useful.

it's a terrible headspace to be in. his boundaries were knocked down by his own hands, and he has to fix them with no idea how it got so bad in the first place.

then there's the matter of the DRK questline. during the quests up to 50, he and fray argued a lot because soba had no answer to "why does it have to be you?" but he kept helping anyway. his esteem asks the question: "what will you do when you aren't useful anymore?" and he had no answer still. his esteem is the selfish part of himself that he never allowed to grow when he had other things to worry about. were his siblings safe? is his crew well fed? will the wind keep while we sail? will there be a fight and how many will die from it? what will happen to the star if he fails? hydaelyn needs him, he can't turn back now because things are hard.

he learns, eventually, slowly, that he it's not his usefulness that makes people want him around. it's not about how well he can fight or how smart he is that makes him needed, it's his smile. how loud he laughs. how resolute his loyalty is. how kind he can be in the face of tragedy. he's needed and wanted not because he's hydaelyn's champion, rather that he's steadfast, and if he's simply asked for help, he'll be there.

it just takes a while for him to get there, is all.

if we're going based on when i started shipping them, it's been a couple of years by now. they just crashed into me one night and now they are my everything.

character-wise tho, pipin had been harboring a crush on soba since the grand melee back in heavensward- hard not to like a guy who can beat your dad in one on one combat (even though pipin knows raubahn would've won if he had both arms), especially when the first real meeting was when soba was sopping wet and furious at being accused of murder on top of all of his friends sacrificing themselves for him, and the second meeting was helping break raubahn out of prison. neither meetings are conducive to catching crushes. but, it is incredibly easy to catch feelings for a guy who smiles so confidently, who is sure of himself and where he stands, and is so ardent in his loyalty to his friends and allies that a little seed was planted and nurtured whenever soba deigned to visit ul'dah. (no one would've been upset if he put ul'dah out of sight and mind considering how the bloody banquet went, but soba wasn't going to let lolorito have any sort of long standing victory over him, you see.)

soba didn't realize he liked pipin until much, much later. he isn't the kind of person to pick up on romantic undertones. making friends is easy. figuring out someone may love him? that's much harder, so he needs someone to be upfront with their emotions surrounding him so he can put himself in that line of thought. now, this doesn't mean he didn't love spending time with pipin. he thought that pipin's dry humor was sharp and hilarious, and soba was always willing to poke at pipin's bubble to get an honest reaction out of him, or even challenge him to small contests whether he won or not because he liked spending time with him!

some would say that's akin to going on dates, but not sosoban checheban. he wasn't thinking that at all.

so, pipin sits on his feelings for a few years, soba is clueless for those few years, and it isn't until after the events of endwalker that soba starts realizing that he might actually like like pipin. crazy. it doesn't solidify until soba moves to ul'dah permanently, finally choosing to not live out of inn rooms and settle somewhere that he can have a permanent address (and despair over taxes), and pipin takes him to a festival happening in the city where he sees how pipin smiles at him that the thoughts of romance and love barrel into him and leave him embarrassed and tongue tied.

there was no dramatic declaration of love between them. neither of them are into such things. no, they didn't tell each other until soba brought it up over a night of drinking, and asking pipin what he'd do if he loved an adventurer, someone who doesn't stay in one place for too long. and pipin says that he wouldn't mind at all, but he would greatly appreciate it if that adventurer would take better care of himself since he can't go on those travels himself.

it's a slow start to a relationship. they're both testing waters and lowering defenses, and they both decided to keep it a secret until they were both more comfortable with telling others.

that does not stop the confusion of raubahn congratulating them getting together, or why nanamo keeps sending them extravagant gifts to celebrate their coming together.

aside from a healthy amount of superstitions soba's had ingrained in his head since he was a sailor (he doesn't say goodbye, looking for red skies, tossing coins into ports if he's on a boat or ship), one of soba's main fears is a day with no wind which makes no sense on land because it doesn't matter! but a ship becalmed? that's a nightmare in the making. stranded out in the middle of nowhere with water you can't drink and no relief from the sun is a terrifying thought in general, so much so that it followed soba to a life on land. by extension, he would never whistle on a ship (bad luck, you see, to try and challenge the wind) unless there's little to no wind, and then he'll whistle a tune to try whip up a storm.

he also has a fear of being handed a drink that he doesn't know the origins of or hasn't watched it be poured, for incredibly understandable reasons! terrible things have happened to him because of a drink that he hasn't vetted himself. his experiences with drinks in eorzea spurred him into partaking in mithridatism again, something he thought he wouldn't have to do again, but ul'dah proved him So Wrong about that.