The term was originally used in reference to being "all-in" on Tampa Bay Buccaneers running back Doug Martin, who is known as the muscle hamster. However, the term sounds much more like putting on a condom.
"You don't know where that chick has been. Better hang your hat on the muscle hamster."
Boys who enjoy yaoi (a genre in Japan that contains sexual and/or romantic relations between two men); literally translates to "rotten boy"; corresponding female : fujoshi