Okay, I'm going to start working on this NOW before it gets to be too huge for me to attempt. XD
Akito:
Canon Relationships [outside of camp]
Ikki: Akito's crush and "special person." Loves him after he rescued him from his brother, and again after defending him again after he came looking for him. Is probably the one person in the world Akito really trusts. Lives in the same house with him after being rescued in canon.
Kaito: Akito's older brother. Kaito is responsible for a lot of bad things in Akito's life... but despite this, Akito can't bring himself to hate him, or stop him when he starts abusing him. Was resigned to being his "pet" until rescued by Ikki.
Camp Relationships
Tomo: Talked to her once. A bit surprised at her resistance to the "if you like someone, give them HUGS!" idea.
Chizuru: Met her and traded names! They didn't really talk or get the chance to do much else. XD
Ikkaku: Recognizes that's he angry, and bald.
Anya: Agrees with her camp really isn't that bad.
Buffy: Was grateful for the s'mores he got from her.
Cher: Has gotten the impression she's under a lot of stress, but has only met her once.
Allen: Met while he was in Youji's body. Thought he was very nice, and took the opportunity to play with his catears. 8D
Update: Met him while in his normal body, and he became the second person Akito hugged at camp! Likes him lots now. :D
Kon: Met him while he was upset at Miri. Doesn't understand why he'd respond to someone like that, and is worried because he himself barely knows what's going on too... Update: Talked with Kon, and while they didn't really discuss the time before, he got new reason to be optimistic of him.
Near: Responded to his poll about campers, and has gotten the impression Near must be a pretty smart person.
Lady: Doesn't know her name yet, but had a talk with her while she had catgirl features. XD
Carrot: Has become relatively good friends with him rather quickly! Was offered a chance to be let out of the straitjacket by him, but declined. Is sorta ignoring the fact (and thus the emo around) the fact he's a police officer.
Etna: Was one of the first people he met at camp, and was surprised when Etna told him she was at least a thousand years old. Had to be told she was a demon. XD
Da Qiao: Thinks she's very sweet and that her cooking is great! 8D Was fed by her when he was hungry.
Ying: Was the first person he met at camp! Isn't sure what to think of her kittens, but thinks she's nice.
Sun Ce: Met him and struck up a good friendship rather quickly. Is the first DW character he's really grasped is from "the past," but thinks that cool because he can tell him about "the future".
Simon Tam: Was impressed by him because he was the first to notice the "double personality" thing out on his own, and referred to it in medical terms.
Fletcher: Met while he had the age virus, and thus won't recognize him now that he's back to how he was. XD Was the first person to get a sorta-direct answer to the split personality question through patient and direct questioning.
Nishi: Akito isn't sure what to think about Nishi for the moment. He get's the impression he's smart, but also a little dangerous. Has resolved not to think too much about it.
Kira: Met him, but not sure what to think about him yet.
Mirialla: Met her, and "defended" her from being chewed out by Kon. Doesn't really have an opinion about her yet though.
Zim: Met him, but didn't even have a chance to go "what's wrong with this kid?" Is one of the few people he's referred to himself in plural to though. "We don't stink!"
Emilio: Thought he seemed friendly until he started making sexual innuendos and startled him. Changed into Agito in front of him with nary a regret.
Gwendal: Told him about his cute catboy experiences at camp so far. XD
Youji: Met him while he was in Allen's body, and got yelled at by him. Is armed with the knowledge he might like having his ears fluffed. 8D
Naruto: Has met twice. Thought he was friendly and kind, but no real opinion beyond that.
Ari: Received all sorts of advice from him, and Akito likes him a lot for it! Has been the only person Akito's hugged at camp so far.
Ash Ketchum: Another instant friend! He likes pikachu lots too! He won't eat any food from him though, as per Ari's advice.
Kodachi: Met, but sorta gave the wrong impression about himself (being rich) to her, he thinks. "It's true I did move into a bigger place recently, but my previous place was like, four by four feet big, and circular shaped, made of iron." Has gotten the impression they're from different worlds (standard of living-wise), but is trying to ignore that.
Ranma: Thinks he's got bad ideas about how to show affection re: Akane.
Akane: They met, and he thought she seemed nice, but hasn't really thought much beyond that about her.
Death: Was one of the first people he got advice from, but hasn't realized she's... Death.
Delirium: Met her for a few seconds and thought she was cute. Received a candle from her.
Lex Luthor: Met, and had a philosophical discussion with him. A bit perplexed by his ideas of "becoming stronger"... he can't disagree with it in theory, but trying to think of good examples for it makes his head hurt.
Glinda: Gave her the advice he received from Ari! Thought she seemed pretty nice.
Zatch: Borrowed his marbles and promised not to lose them. Also explained his eyepatch and its function to him, sorta. Update: Third person for Akito to hug at camp!
Rosalyn: Has a good impression of her, because she was nice and didn't question at all switching right in front of her.
Rin: Met her deaged, and knows her as Sohma Isuzu. Thought she was very cute, though a tiny bit disappointed she wouldn't draw him when he asked.
Norma: Performed an A-T stunt for her! Is also kinda happy she gave him a nickname, it's the first time someone's called him by one.
Haruhi: Get's the impression she's not quick at figuring things out, because she was completely and totally confused by Akito talking about Agito until he finally switched in front of her. But, he really likes her overall attitude and thinks she's really fun and cool.
Summary for Akito:
High affection for: Carrot, Allen, Ari, Ash, Zatch
High opinion in general of/grateful to: Simon, Kodachi, Buffy, Da Qiao, Norma
Is cautious of: Lex Luthor, Nishi
Has a "low" opinion of: Emilio
[note: I say "low" opinion because it's very difficult, maybe impossible, to get Akito to actually hate/dislike someone.]
Agito:
[Note: I could give impressions for Agito for everyone Akito has met as well, but I'm deciding to keep Agito's listed relationships as people he's actually talked to while "out," not just impressions he's formed while Akito has been talking.]
Canon Relationships
Ikki: The fucking idiot crow. Thinks he's incompetent and quite possibly the worst A-T user he's ever seen, even if he is starting to be a little surprised by him as his skills begin improving. Still, he'd rather die than admit that. There's something about Ikki that sets him off when they first meet... But even then, Agito refuses to regard him as anything more than another idiot.
Kaito: It'd probably be best to say they have a weird sort of "business relationship." Kaito needs Agito to grind "criminals" up, Agito's more than happy to oblige. Agito also finds amusing the sort of irony that Kaito is possessive/abusive to Akito while also fearing Agito. Still, he has no regard for Kaito beyond that, and will happily tear him up too just as easily.
Camp Relationships
Ikkaku: Hates him for being a fucking moron and playing with his eyepatch. But meeting Ikkaku DID give him an ego boost, as he clearly found out about Agito because of what he did to Natsuo. Wouldn't mind carving some nice scars into that bald head of his.
Simon Tam: Thinks he's a pretentious bastard and refuses to talk with him.
Nishi: Has picked up Nishi's much more knowledgable than he lets on. Thinks he's a psychotic bastard, but whatever... so's he. Nickname: Mr. Sly Grin.
Emilio: Perverted bastard.
Natsuo and Youji: Tried fighting Natsuo after taking one of his remarks a little personally, but gave up when he realized they couldn't feel PAIN. (Like hell he's gonna fight someone who's not going to have the courtesy to at least wince, that's just insulting.) Thinks all catboys/catgirls are pain-unfeeling because of the experience.
Gan Ning: Actually felt a little guilty that Gan Ning got bitched out by Sun Ce for exchanging insults and not giving them the chance to settle things themselves, but also didn't care enough to correct him.
Updated: After a talk with him again, has come to the conclusion: "This guy's a fucking idiot... my kind of idiot, though." Nickname: Bell-boy.
Sun Ce: Picked up he thought he was Akito, didn't bother to correct him either. (Let the fucker figure it out for himself...)
Delirium: Met her, and got mildly freaked out. Has gathered she's not to be fucked with too much.
Rosalyn: Has a cautious/bad image of her because he switched right in front of her and she barely noticed (Obviously hiding what she thinks and can't be trusted). Was mildly surprised to hear about people at camp with 'genocide-level' powers from her. Update: Rosalyn earned his ire when she accused him of "possessing" Akito. The results of their fight has only more so set him off-balance.
Rin: Talked to her when she was deaged for about a second before deciding Akito would probably be better at talking to a little girl. Fuck.
Norma: Hates her for talking Akito into near-injuring himself for her amusement, even if she did heal them and Akito did want to do it. X(
Cher: Received coffee from her. Had an actual almost civil conversation with her. Could probably careless about her, of course, but first time that's happened, really.
Haruhi: Was a bit intrigued by her. She's probably the first female to ever react to him with: "don't tell me what to fucking do". (At the very least, the first ordinary seeming schoolgirl with apparently no fighting ability to do that.) Suspects she's either capable of more than she lets on, or is just that much of an idiot (leaning towards "idiot"). Update: Haruhi has grown on Agito to some extent. She's probably the easiest person he can talk to, or at least the person he can talk to the longest before leaving in disgust or having it turn into a volley of swearing. He hasn't even realized that his opinion of her has gone up (he probably would've stopped if he did).
Summary for Agito:
Has a "high" opinion of: Nishi, Haruhi
Neutral: Gan Ning, Cher, Lupin
Genuinely off-set by: Delirium
Hates/Thinks is a fucking retard: Everyone else
Burning hatred for: Rosalyn
[note: I say "high" opinion because it's very difficult, maybe impossible, for Agito to actually have respect for anyone.]