Mordecai and the Rigbys
Two-man (well, one blue jay, one raccoon), two guitar band featured in the eponymous episode of animated TV comedy Regular Show (first aired 22 Nov. 2010). They have shirts before they learn songs. Thanks to a spilled soda and a gramophone-based time machine, they learn to rock from their future selves, who are successful musicians with British accents. But then they find that their future selves are just lip-synchers. Mordecai breaks up the band, keeping his integrity while losing the girl. Rock be a cruel mistress, my bird friend.
Other names considered during the band's formation: Cool Dudes, Face Punch, Ren's Trek, Helicopter Crash, and Mustache Cash Stash. We agree with Mordecai--should have used the last one.
Later in the series, in the imaginatively titled "Return of Mordecai and the Rigbys," they reform as a real band with additional members (including Benson on drums), break up, and then become an a cappella act.