White Magnum
The practice of inserting a penis into anus/rectum and ejaculating of another who is about to defecate.
Dean: Do make sure you eat plenty of fibre today
Sally: Why would that be?
Dean: So that when I put my cock in your ass and cum, I can give you a white magnum
Sally: Why would that be?
Dean: So that when I put my cock in your ass and cum, I can give you a white magnum