Body parts being used for not inherently/obviously sexual situations. Examples would include using a vagina to store objects, using a penis to hang cloth, or using breasts as a sign board.
This guy gets it. You should read some Marquis de Sade if you haven't, someone who got the base pleasure of obscenity and defilement for its own sake and writes in a very fun way. Guy was writing about drinking tea using loli milk enemas in the 1790s