Maybe it should be odd, but Derek - folding his arms, not as a sign of hostility but as one of relative ease - merely listens with the beginnings of amusement on his face, one brow quirking when Stiles singles him out. Innocuously, he shrugs.

"I'm a social butterfly," he tells him, conversationally serious. His mouth twitches upwards, and then he continues, more thoughtfully. "Seems like she's just being inclusive."

Stiles has his suspicions, yes, but Derek isn't about to confirm them. Not yet.