[He pulls off a faux-offended expression as he puts his own hand over the place where she slapped him, but then he breaks into laughter again.]

I know, I know! It's just - [He calms himself down a bit.] - I just thought of this giant purple chair, in the middle of the street, right? And everyone's tryin' to climb on top of it...

[He wriggles a bit underneath her as he makes vague climbing motions with his hands.]