He stiffens up slightly under their touch, but after a few moments, he manages to relax, smiling just slightly. He's getting used to touch. It's something he and his brother and Gaster shared a lot, and now he's just applying it to others.

"...Right. You know me too, don't you? Can I ask... how? I mean, what was I like?"

Probably nothing like he is now. He doesn't feel bad asking that, now that he knows they can't sleep. He may as well distract them.