The smile he gives her is, by nature of the circumstances, a little goofy. Scully's picked the right answer, no matter how tempting a puppy might be; being wanted is as good as being touched, and right now, with her hand snarled near his scalp, he's both.

He nudges her free hand away from her panties, sliding further down the bed so his mouth can land a kiss just below her navel. "Let me."

It's an old trick, and a stupid one, and he never gets tired of it. Catching the elastic of her panties between his teeth, he starts pulling them down. At some point, his hands will take over, but for now, the effort of dragging them down over her pussy is its own reward.