Harry:
Switch. He likes feeling high mighty but also doesn't mind chilling on the low.
Ron:
Switch. Mostly likes the top. He gets fussy and squeamish when he's bottom.
Draco:
Top. Will only go to the bottom if you ask. He won't admit that it's cool down there.
Fred:
Top. Only likes top, he likes looking down at you like a sucker.
George:
Switch. He prefers bottom. He thinks it's fun down there.
Neville:
Bottom. He wouldn't mind being on top if you asked. When he is top it's fun.
Tom:
Top. Only top. Will never be bottom.
Cedric:
Switch. Mostly top.
Oliver:
Switch. Mostly top, he gets whiny and stubborn when he's bottom.
Seamus:
He thinks he belongs on the top bunk but he really belongs on the bottom.
Dean:
Switch. He prefers bottom. He likes watching you play on top.