Sleeper Peeper

A boner that arises at the moment when you are close to falling asleep, but becomes so uncomfortable that you must push back your sleep and instead focus on getting the boner flaccid. Typically one rids themselves of this type of erection by removing underwear or whatever they were sleeping in, and then not letting the peeper touch anywhere else, as that may keep the boner going. It may take awhile.

Dude 1: Yo man I got no sleep last night.
Dude 2: Damn that sucks. What happened?
Dude 1: Sleeper peeper bro. Shit didn't go away for hours.
Dude 2: I feel you dude.