Benjy will definitely know Desi since he rooms with Kermit so he'll be friendly!
Benjy would know who she is since her brother plays Quidditch. He'd be nice enough if their paths cross, but I don't know how often they'd cross?
Yep. Cenric = no = hate. Haha.
Yeaaah. They'd definitely know each other because they're in the same year, but idk if they'd be friends or just friendly? Benjy isn't outright mean to people who annoy him so he'd be nice to Bedivere but I guess we'll just have to have them interact to know for sure if their personalities mesh.
As for Peter, he probably knows him as the kid that follows after James and Sirius. lol.