To
apply pressure to one's partner's sphincter during sex in order to gauge their reaction. If they react positively, then one has
implicit permission to insert a finger or thumb into the anus.
On the contrary, if one's partner reacts negatively, then access to the anus has been denied.
Guy 1: So I was banging this chick from behind the other night, and I rang her bell with my
pinky finger.
Guy 2: haha, we know what happens when you ring the bell
Guy 1: yeah, she moaned heavily, so
I slipped it right in there and
came buckets.