This is a photo from "The Itchy Brain Simulation." It's Episode 7 of The Big Bang Theory Season 8.
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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.
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The Big Bang Theory Season 7 Episode 8 Quotes

How those nipples feeling, chief?

Sheldon

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