Hi Chris!
I have tons of characters who I could throw at you but I'll limit it to the youngest and most likely to interact.
Aphie Dawlish - Her full name's Aphrodite, she's a third year Hufflepuff and just a bundle of joy. I'm sure they would be great friends, even if Chris doesn't know it cx
Jeremy Peakes - He's a Fourth year Gryffindor, and is actually an illegitimate Poliakoff though no one really knows that. I can see the two of them getting along, maybe having a friendly rivalry for whatever reason.
um.
Hitame Higurashi - She's my main character, and is a Sixth year Gryffindor. A lot has happened to Hitame and thus she's not exactly very trusting of people. She can be friendly when she wants to be, when someone gets to know her, but most of the time she'll come off as depressed or mean. She is a depressed but she tries her best to keep it from affecting her and others around her. I think she would be like an older sister type of person to Chris. She actually loves first years and younger kids, believe it or not.
I'm also working on a first year, Ravenclaw. Her name's Aeron Greyback, I'm not sure when she's going to be up though so I'll let you know about her.