[ derek needs a little guidance, here. he's watching stiles and trying to figure out which kind of mood to bring into this conversation, the sort of steps he needs to take; he's a little worried that stiles is going to try to pick a fight, so he doesn't know if he needs to keep his guard up. he doesn't know if stiles is going to just-- ask to get this bondage thing over and done with or if he's going to ask derek to put it off until tomorrow. he doesn't know what to expect at all, and that unsettles him, because reading stiles is something he's supposed to be good at.

when stiles slips straight into guilt, derek... well, derek should have seen that coming. he mentions the cat, and derek looks over his shoulder to where she's springing up onto the couch in the living room behind them, tearing up the seat with her claws to get it comfortable. he looks back to stiles, heading further into the room, his hand a little sweaty around black plastic handles. ]

You smell bad, so.

[ he sets the bag down by the bed, then - hesitates, realizing that might have come across as an insult. he looks at stiles, wide-eyed, then softly shakes his head. ]

I mean - you smell anxious. She seemed worried, when I saw her. Like she knows something's wrong.

[ or that something's going to happen, at least. derek toes off his boots without bothering to unlace them, and he sits on the edge of the bed, looking at stiles with a sympathetic fondness. he doesn't hold any grudge about their conversation at the garage, and he hopes that stiles doesn't, either. ]

So... she's probably just scared. Not upset. She'll come good, when you do.