This is a photo from "The Itchy Brain Simulation." It's Episode 7 of The Big Bang Theory Season 8.
Sheldon makes Leonard pays for a past mistake on The Big Bang Theory. "The Itchy Brain Simulation" is the eighth episode of the show's seventh season.

The Big Bang Theory Season 7 Episode 8 Quotes

How those nipples feeling, chief?


Leonard: How about that? Sheldon's being reasonable.
Penny: Yeah, it's freaking me out. I'm gonna go.