Hokay, so I like to do this: list every other character and give a general impression of what my character may think of them and thoughts for their general relationships. Hopefully if you can give me a bit more information back, we'll know where we stand and get an idea for how things might unfold. As the university's first point of contact with its young witches, Sebastian is probably on first-name, mostly-professional terms with each of the witches. I'm expecting he doesn't really have any awareness of the hunters.
Adelaide Ruine: – (does Adelaide go to the university?)
Katherine Pierce: distrust. The family is fiercely insular and doesn't really embrace the wider community and he doesn't expect much more from her – he's keeping an eye on her. But, hey, she's hot!
Matthew Friel: sweet kid, maybe a bit nervy. He'll probably turn out fine...
Graham Bishop: he comes from the psycho family and seems evasive. Not to be trusted. Another one he's keeping an eye on.
Pazel Razi: nice kid. If he was a bit older, they'd probably be friends. Comes from a decent but unfortunate family. Slightly depends on when Paz found/finds out about his magic blood, though.
Emily Burkes: who? So, she's a student on campus. That's nice.
Maximilienne Barrande: Sebastian probably dimly remembers her name as an old enemy back in Europe, but may or may not know that she has also moved to the US.
Rosenkreuz: a reasonably famous enemy, but Sebastian naturally has no idea as to hir identity.