Otaru is reunited with Lime, Cherry, and Bloodberry, female androids known as marionettes, who have returned to his side. The Faust marionettes, reformed to some extent, are sent to live with Otaru and his friends to gain a deeper understanding of human behavior, alongside the new marionette Marine, who possesses a unique ability. What sets these marionettes apart is their possession of a maiden circuit, which enables them to experience emotions.