Omaha slip and slide is when you do your girl in the shower, bust a nut inside her, and she let's the jizz slip down her leg, catches it in a shot glass and let's the jizz then slide down her throat.
The westyn is where you take a girl to a staircase and jab ur cock in her throat until she vomits, making her vomit on the stairs, then you blow your load on her face while you knock her in the face, u then throw her body down and ride her down the stairs over her vomit while you shit on her
jason used The Slip' n Slide on his girlfriend last night, it was fun to watch