, probably originally short for "kill a kitten". In prison lingo, it means to do this in front of a female prison guard to traumatize and disgust them.
A girl can also kill a guy, and although this is a flirt
ing technique rather than masturbating. Specifically, a girl sits where the target guy can watch her mess with her hair. Most effective when the girl is sleeveless, and leaning back somewhat, giving him a great view of her upper arms and upper body figure (and a hit of underarm pheromones) with slow sexually-loaded stroking of the hair and sometimes neck.
The felons got their jollies by killing the new female prison guards.
(Guy to himself) Damm, that girl is killing me again. Man! I'm getting a serious boner
! Uhh... gotta use peripherals...