They are making out, in a manner the script even goes so far as to call "heated," and Chris is really, really wishing he spent more of his time making out with people he didn't work with so he'd have some kind of frame of reference for this type of thing.

"What, you don't roll around with all your clothes on when you're having sex?" Darren asks, and Chris snorts into his shoulder. "Because that's, like, the only way I'll do it. Either roll or go home."