rack sack
The act of ejaculating onto a female's breasts.
Dustin: So dude did you try that new thing with her tits? A rack sack?
Mitch: Oh I totally rack sacked her.
Mitch: Oh I totally rack sacked her.
Sack Rack
When a guy gets kicked, hit, or otherwise sustains pain to the groin area.
Sally kicked Jimmy in the balls. "That was a sack rack".