Apophallation

Apophallation is a technique used by some slugs following intercourse.

The slugs (which are hermaphroditic) have relatively large penises which wrap around each other in a tight spiral. They can have difficulty separating afterwards. Should that be the case, the solution is for the slug to gnaw off either its own, or its partner's penis, making separation possible. No replacement penis grows. The apophallated slug adopts a purely female function.