[Oh god. A jolt of grief shoots through him, and he sits up properly, taking Derek's face in his hands.]

Derek. I would never, ever. Ever. Do that to you. Don't you get it, Grumpy? I'm nuts about you. Whatever you need...whatever you need to feel comfortable, it's yours. Even...even if it's not making out or doing anything. Seriously. Look at me, Derek. You've been listening in on my emotions for weeks now.

Listen in now.

[And every word is the hand-to-god truth. Stiles' heartbeat is elevated, yes, but that's from their activities. His arousal is overwhelming, yes. But it's tempered by genuine love and concern for his wolf.]