A euphemism for not getting any sex, and possibly doing another activity (ie: stress baking) to relieve the stress of celibacy.
Cindy: What's up, Jon?
Jon: Just hanging out, baking cupcakes.
Cindy: Oh, I love cupcakes! Save me some!
Jon: That's not what I...oh, never mind. Wanna do it?
Cindy: Not really
Jon: Then I guess I'll keep baking cupcakes.