Happy Endings - Season 1 Episode 6 -

Alex has a mouse in her apartment and asks Dave to come over and get rid of it humanely. While there, Dave falls in love with their old place. He lets the mouse go so he can spend more time there. Penny takes a Krav Maga class. Jane joins the class, is way too intense, and kicks the crap out of Penny. Max accuses Brad of being a "gay-cist".