Hello Megtoo! I'm Becca and I have five kids here. (Yeah, I realize I might be crazy but, in my defense, I was injured and writing apps kept me from going batshit insane from all the bed rest.)
The first is Stella Fawcett (astellaidea) who is a 6th year Ravenclaw. I suspect she will probably know Keegan quite well as she is an honorary Hufflepuff--she's as close with H6 as she is with R6. Stella is bubbly and friendly and boy crazy (she did snog Cedric right before school started, but we won't tell Kee that), and staunchly Team Cedric. She's trying not to be too anti-Potter since it only gives him more attention, but we will see how long that lasts.
Then I have Amelia Higgs (misshiggstoyou), who is a 5th year Slytherin. She'll share classes with Keegan, but probably finds her loud and annoying and abrasive (Amelia thinks this about, um, most people). Both being anti-Potter might be the first thing they've ever agreed on.
Ava Rosier (pretensity) is a 7th year Gryffindor and the daughter of dead Death Eater Evan Rosier. She's half-blooded but forced by her grandparents to keep that a secret and been raised to believe that her own blood is dirty. She's pretty screwed up, but it is mostly internalized. Outwardly, she is quiet but kind. But she's also Team Harry, so I doubt Keegan much cares :P
Elena Gregorovitch (caffiendishly) is a 6th year from Durmstrang. She functions in a pretty constant state of deadpan sarcasm. She's almost never serious but it can be reeeeeeally hard to tell since the delivery is always the same. She's snarky, coffee-obsessed, and kind apathetic about most things. She's one of the lads, a Beater, and Team Viktor because he's her pal.
Elodie Chevalier (this journal) is a 7th year from Beauxbatons. She's sort of like French Hermione/French Rory Gilmore because she's super intense, and type-A, and works incredibly hard at everything. She can be fun when she remembers to relax, however. Also, she's been dating Calvin Fawcett (Stella's older brother, who may or may not be responsible for the badges...), since the summer. She's Team Fleur.