Colorado Snowman
When a man masturbates during the winter but does not clean any of the residue, semen or "snow", off during the entire winter eventually leading to a point of no return where the penis is no longer visible and only a snowman shaped figure can be made out of the residue near the end of the winter.
Did ya hear about Earl? His mom caught with a Colorado Snowman and now he has to repent for his sins!... and take a bath!