"W-Well.. Thank you, but it's kind of hard to tell from the outside..!"

At least she's looking with her eyes! With her eyes, for sure. After all, Madoka's hands are very much occupied with holding the cat! Although she's stopped holding Maru close to her chest and is holding him out a little now, as if she's silently telling the cat to go for it. She knows Maru's a good kitty, so surely he'll just grab it to take a look rather than hurt the poor penguin-like thing, right?