The act of ejaculating into a man's penis slit and when that man ejaculates he will be ejaculating twice as much semen (his and his partners).

When you eat dirt for the first time and leave your family to build a shack in the woods

When one finally becomes intimate with their partner and then after a romantic moment, then inserts their penis into what resembling what looks and feels like a dry mountain less dessert from Dune.