Bum Tunnel 

The process by which a bum is born. I.e., a man who creates baby mamas or abuses girls and women physically or verbally had to bum tunnel out of the womb into the world.

Future and Nick Cannon and R. Kelly shouldn't have bum tunneled their way into existence.
These little bay boys bum tunnel their way out into into a crib for the rest of their lives.

Bum Tunnel by Cree Seven January 15, 2023

Bum Tunnel 

The term used when two people of any sex create a tunnel by pressing their bare bum cheeks together, usually for the purpose of a third male party to insert their penis for sexual pleasure.

“Ryan rang at lunchtime to invite Mike and i round tonight for a bum tunnel and a curry”

George “Would you like my wife and I to bum tunnel you?

Me “no”

Bum Tunnel by Leviathan Porkchop June 25, 2021

bum tunnel 

A bum tunnel is the term used when a persons anus can be used as a pathway for trains and buses.

'Man, her asshole was so loose, a definite bum tunnel, i could have parked a double decker in that space.'

bum tunnel by HYoung119 July 1, 2015