The act of smoking marijuana while doing laundry, followed by placing a batch of freshly dried/warm shirts upon the face resulting in a prolonged sensation of bliss.
Friend: What are you up to this afternoon?
Other friend: Shirting my ass off until all my laundry is done.
When a frat surrounds a celeb at a bar and encourages him/her to go completely topless. The topless celeb is rewarded with a shirt representingthe letters of the fraternity.
When one has to take off their shirt due to the intestinal pain that is due to... (enter possible cause for the diarrhea that tested your accuracy and ability to puke through your legs whilst painting the bowl... impossible)