Derek doesn't do 'buddies', Stiles. Might want to accept that before any feelings get hurt here... Namely yours.

He doesn't look particularly happy about the bigger piece, but whatever. There's a limit of how much bitching he'll do with someone who is just too thick to get it. So he takes the plate with the pie, leaves his coffee black and then raises a brow at Stiles.

"No." A pause. "It'll ruin it."