Safe sex, alternately known as vaultaic reproduction, is the collective term for the courtship and mating habits of lock boxes, bank vaults, and other breeds of locked storage units, although the term is most commonly associated with household safes, specifically portable safes. Alternately, safe sex is a slang term describing human Sexual Intercourse on top of, inside, or otherwise utilizing one or more of the aforementioned storage units. It is not to be confused with safe hex, a series of precautions used to prevent the spread of pornographically transmitted diseases (PTD's) among humans.