Maxwell: Jonathan is friends with Izzy so that would probably translate well over into him being friends with Max! He could be hesitant around him at first, because his last experience with jocky dudes was the worst, but once he was around him enough he'd love him. Jonathan is very friendly and personable himself, so their personalities would mesh well together. Plus, they're in the same faction and maybe Max could teach him to surf? He needs new hobbies. | Finn would know Max through Izzy. Finn is her father's TA and they had a weird relationship in which he's secretly interested in her, but behaves like a complete ass around her as a result. Not sure if Max would like him, but Finn is probably wary of him because competish, k?
Meredith: Obvs Jonathan loves her and she will have to put up with him being a teensy bit needy over the next few months. Mostly because he can't believe she's here and will need constant reassurance of that. | Finn is only a year older, but I imagine they get along really well since Meredith is nice and not in your face about things. | Charlie is in Meredith's faction and probably thinks she's dull so she's take to irritating her.
Nikolai: Finn would know him because he considers Olivier a friend and spends time with him instead and outside of the school setting. So his friendship would probably extend to Nikolai as well. | Jonathan is one of his new students so he would know him that way!
Seraphina: Finn thinks of Sera as another sister, basically. I don't know how well she took to Jule's intense bb brother at first, but Finn loves Jules and that's apparent and he would have always been accepting of their relationship. | Jonathan is a new student here so he might end up in Guidance now and again while he adjusts. Anyone he comes across who's comfortable in their sexuality will have his awe and envy so he might gravitate towards her a bit because he'd want to talk to her about it but would end up talking about trivial shit. | Charlie mostly thinks she's hot but keeps her conversation with her friendly because Jules is her friend.
Summer: Summer and Charlie are both Offensive students and they're only a year apart. I can see them actually getting along very well because they have similar personalities and she would like getting into trouble with her. | I'm not sure how Jonathan would know her but if their paths crossed he would be friendly! | Finn is a TA and probably doesn't have much contact because he's in a different specialty. He is friends with her best friend Xander though, so maybe through him?