The act of receiving oral sex from a female to the point where you are about to ejaculate so then you pull out and beat the top of her head with your dick while ejaculating all in her hair.
Jose: So did you try "Cock on the Roof" on your girl yet?
Quan: Hell yeah I did! Gave her a head concussion!
Quan: Hell yeah I did! Gave her a head concussion!
by @LittleBigMan October 06, 2016