He'd be a good way to tell people if you're open to visitors too probably. Just flip him. [He's only half joking with that suggestion before Peter remembers the second gift still in his hands.

He shakes it out a little bit, holding up a long sleeve shirt for Otto.

I know you're a lot... fancier than I am, but I thought a shirt to work in or whatever with a dumb joke on it would be fun?

[He turns the black shirt so Otto can see the shirt. The design on the front was drawn carefully by these little rat hands Peter himself.]