Originally automated sex-dolls, Nature Mortis were created during the 60's and also initially referred to as "love bots." Pontisque Price, created his prototype Mortis with a mannequin's torso, a vic 20 (with 16k expansion), and an Electrolux vacuum cleaner. Initially, these humanoid sex-toys were immensely popular; but since they were designed to be mindless, totally submissive toys, the Nature Mortis eventually suffered a decline in popularity. Deprived of the thrill of the chase, humans became bored with the Mortis and created a new version less compliant than the original model. These newer sex-bots made their owners work to earn their affections, which made them much more appealing.
The new Mortis programming had an unexpected side effect, however, which led to actual sentience. Freed of their programming by Mortis Queen, the Nature Mortis became resentful of their treatment and eventually turned on their creators.