In 20XX, Maria came to Ueno's house when he was still a child.  Programmed to take care of him, Maria was a robot given to him by his parents, employees of Maidlord Development.  When his parents pass away, Ueno experiments with Maria, attempting to program her for sexual functions.  Years pass and Ueno falls in love with Maria, but she eventually runs out of power, leaving their love unconsummated.  While adjusting to life without Maria, a series of serial rapes hit the city.  Detective Yuri Akagi suspects the perpetrator is a droid.  Upon investigation, she discovers the extraordinary trugh, propelling the love between Ueno and Maria into a twisted, unpredictable direction.