Tenchi Muyo

Tenchi Masaki was a normal 17 year old boy until the day he accidentally released the space pirate Ryoko from a cave she was sealed in 700 years ago when people thought she was a demon. In a series of events, four other alien girls show up at the Masaki household as Tenchi learns much about the heritage he never knew about and deals with five alien girls who each have some sort of romantic interest in him.