The act where a male assumes the top position during the sexual act of 69ing, opposed to the usual bottom position where the female is on top. This can be also referred to as “calling top bunk”, and “top bunking” if used as a verb.
(verb)- To hook up with a person in the top bunk of a bunk bed. Can be modified into a double-bunk if there is another couple hooking up on the bottom bunk.