A straight male who attempts to protect himself from rape by clenching his buttcheeks together. Can commonly be observed in prison showers.
Prisoner 1: Look at Billy over there... he’s clenching his cheeks real tight.
Prisoner 2: Must be cause he dropped the soap... he must be a clench defender.
Tyrone: Shit mayne... I’m still comin for that double-wide surprise *inhales* gawd dayummm.