I think they just sort of roll around. I haven't seen any eyes or anything either. It's like they're literal balls of fur.

[Jamie grimaced a little as she picked the things up - just because they weren't chewing people's arms off didn't mean they might not be hiding other unpleasant surprises, and cuddling with them seemed to him like a poor idea.] Should you be getting that friendly with 'em? We don't even know what they are. What if they have fleas or something?