Ooh, this is fun! I've actually spent so much time thinking about this. xD
I may have to re-edit this after having played P4. Also, I'm doing these based on P3P social links, as I'm sure you would have included them had this been posted now.

I: Aigis: I JUST LOVE HER crying heart Honestly, I would prefer to date her over any of the guys if I could, probably because of her incredible dedication and adorableness and her badassness in FES. And she seemed to have feelings for the female main character, so it wouldn't be totally hopeless. sweatdrop

II: Bebe: He's so cute and nice! He would be so easy to be friends with. whee I would have dated him if it were possible. I don't like sewing but I would join the fashion club anyway for him. heart

III: Fuuka: When I was doing her S. Link in P3P with the female main character, she just seemed like the type of person who I would become friends with IRL. She is so kind-hearted and cute. I would so make cookies with her. xD

IV: Akinari: Once again, when I was doing his S. Link I felt that we would actually be friends if he existed. He's such an interesting character.

V: Mitsuru: I like her because she has such a tough exterior but when you get to see the vulnerable side of her, she's so adorable. xD "Could I hold your hand? redface " LOL and it would be great to have a friend who could execute my enemies xD

VI: Junpei: I could EASILY be friends with him! We would go to the arcade and to eat ramen all the time. He's like an ideal best friend.

VII: Ryoji: I dunno, I just like him a lot. He's very nice and funny and handsome.

I almost put Yukari but it kind of seems to me like she's always PMSing. <_<'