when 2 men are having sex and the pitcher starts to reach around and jerk off the catcher until he ejaculates in his hand. then the man with the cum-filled hand slides his hands through the other man's hair greasing it back.
"You mind if I give you a dapper dan tonight?"
"Not all good sir."
Adj; The code word for something sweet.
Cooper: Dude, I'm about to smash tonight on my hot a chick Alyssa.
Gary: Dude that's straight up Dapper Dan.