When one man gives another a reach around in the bathroom, while a third man acts as Uatu hiding in the bathtub/shower masterbating while watching. Traditionally, the recipient of the reach around has his head periodically dunked in the toilet, however this isn't required.
Every Tuesday, when they perform a Dirty Girard Adam receives from Ted while Kyle plays Uatu
Stems from the name of, and is synonymous with "The Watcher." An Uatu is any person who observes a sexual act, and 'hides' somewhere in the room and masterbates. The presence of an Uatu may or may not be known to those participating in the sexual act.
Kyle always gets stuck being Uatu when he and his friends perform a Dirty Girard.