Preps are mainly a clique (group) of teenagers or young adults who wear Abercrombie, American Eagle, GAP, AERO, and Hollister, and will socialize with others who are just like them based on their clothing and personality.
Kukmar is a sexual manuever where the male is having anal sex with a female in a reverse cowgirl position,during the sexual activity, the man pulls out and grabs his partner by the legs and rocks her back exposing her open anal cavity for all to see. This is a popular move in porn.