Marco moves his hand to that other ear, managing to pet both with his wrist and his hand by turning it sideways a little.

His grin is a little lopsided as Jean lists the apparently terrifying methods of Levi. All right, he gets it! Who hasn't wanted to hit Jean and Eren a bit when they get into a silly argument, though?

"Maybe you just need to clean better," Marco says mischievously, and then pets the ears in apology. "Still, I guess you're right; he sounds like a pretty serious and intense guy."