The cum
stop refers to the packed poo up a persons
ass that comes from a solid anal sex session, the packed poo acts as a barrier that prevents all cum deposits from going up any further. When the person goes to take a shit for
the first time after the anal sex session the cum stop shit drops from their
ass as they are going to
sit on the toilet and before they get on toilet seat. This free falling shit is known as the cum stop drop.