When one removes his penis from an ass and finds fecal matter attached to the head of his penis.
When Sarah asked me to fuck her in the ass, I didn't realize it was an invitation for a shit helmet. I guess I found out the hard way.
by fav January 23, 2007
(noun) When a lover dumps a Cleveland steamer on the other lover's head, usually by request.
Come on baby, give me shit helmet.
by Antenna Wilde February 14, 2008