After causing a commotion with his last assignment, Falk has been given a desk job, which hardly agrees with his personality, and he ends up accepting an offer from an old friend to buy into a private investigation agency. Another friend of Falk's, Sven, purchased a business in Estonia, and when local gangsters attempted to pressure him into paying protection money, Sven retain...。故事以史上首个自律人型AI「Vivy」为主角,是以「歌声带给众人幸福」为使命的「歌姬」。某日自称来自100年后的AI「松本(マツモト)」突然出现,并表示自己将与Vivy共同修正历史、避免100年后人类与AI发生战争,使Vivy踏上破坏AI的旅途。。