Hot cross bum 

When during doggy-style sex the guy pulls out and jizzes over the girl/guy's arse in the shape of a cross.

Hey, because it's Easter, how about we do a hot cross bum?

Hot cross bum by Nicearse July 7, 2016

Hot-cross bum 

Shooting a rope in a cross formation on someone’s ass.

“Mike gave me a hot-cross bum last night”

Hot-cross bum by Albatt Ross March 16, 2019