Lime, Cherry, and Bloodberry, female-like androids called marionettes, have returned to Otaru's side. The somewhat reformed marionettes of Faust (Tiger, Luchs, and Panther) are sent to stay with Otaru and friends to learn more about being human. Enter a seventh marionette named Marine, who has a mysterious power -- and they all possess the special maiden circuit that allows a marionette to feel emotions!

[Source: AniDB]