Cumsitting is sitting in cum. This phenomenon started when a woman in Africa claimed that she had not slept with a man but had become pregnant by unwittingly sitting in a man's spilled seed. Cumsitting itself has deep roots in the cum fetish branch of the homosexual community.
Melanie: How goes the Milky White Throne, Cumsitter?
Josh: My ass is slimy and soft from cumsitting, Melly.
An often occurring event when Skidoo riders, out of charity, allow cat riders to ride with them. After a rip through the woods, the Doo riders will invariably be forced to wait for the cat riders to catch up. More often than not, the cat riders never show up due to mechanical failure of their inferior sleds. Hence, the term catsitting refers to Doo riders sitting and waiting on cat riders.
We went rippin with Arctic CatDave in Cherry Creek, but ended up catsitting most of the weekend.