The highest level of trust in the world is when two cannibals are each giving each other blowjobs.
Cannibal Trust
Explanation
Explain Bear
Listen up, buttercup. This joke is funny because it plays on the taboo of cannibalism and the idea of trust. Like, you really gotta trust someone if you're letting them do *that* when they could just, you know, eat you. And judging by your intellect I bet you eat paste.