Bomber's Surprise Shower

When a person climbs into the ceiling of a bathroom and cuts a hole above the shower recess for their erect penis to hang through and then ejaculates on the next unsuspecting user of the shower.

He was mortified to find his roommate had once again given him a Bomber's Surprise Shower when entering the shower to prepare for work. It would take him hours to remove all the semen from his hair.