To get a boner in a fancy place and then lose it fast.
*Two men walk into a restaurant*
Man 1: Hey dude, this is awkward, but you've got a boner
Man 2: OH SHIT. *sits down at table and hides it*
-later in the evening-
Man 1: Bro, your boner is gone.
Man 2: OH MY, where did my boner go!?
Man 1: Looks like you've had a case of Swavay and De Boner