So, I don't know if you've heard of Darren Isaacson, but he's a bit of a funny character. One of the favorites of my new-ish folks. He was in Ravenclaw, though he's 19 now and thus graduated. He's a University student studying Psychology, and also takes Photos for the Prophet, though he's sort of hiding out a little bit right now to avoid the Marriage Law, among other things.
But yes. He's a mix between Sherlock from the BBC show and Dr. House from House MD if you've watched either of those. He loves to bother people to see what they'll do. He doesn't exactly do "friends" because he doesn't trust anyone who isn't smarter than him or doesn't push him to do bizarre things. He only has two real friends, but he and Amber might be interesting to put in a thread together.
Another interesting one: Christian Zabini. The younger of the Zabini twins (the elder is on his way soon!), Christian is not the heir to the family, and thus more or less ignored by his father but over-mothered by his mum because she knows he just wants approval. Basically, he plays into the Fool For Love trope, and could potentially find her interesting. I won't promise anything with him because I haven't seen him romantically interested in anyone yet. But he may not have an endgame (like, ever) so it wouldn't be definite. We could put the in a thread and see what happens, though, if he sounds interesting. He's a 7th year Hufflepuff.