Ordinary youth Joe Doe was unexpectedly reborn into an apocalyptic world invaded by beast creatures. He awakened the "Beast Girl Evolution System," which can evolve captured beast creatures into powerful humanoid beast girls. Starting with transforming a stray white cat "Bianca" into an S-rank fire-attribute cat girl, Joe Doe rises as a "Universal Attribute Beast Trainer," aiming to build the strongest harem of beast girls! After being admitted to the top-tier Beast School, Joe faces rival harassment, pursuit by The Abyss Order, and discovers his parents' disappearance is connected to the mysterious "Beast Frenzy" plan. With the help of his companions - the sharp-tongued cat girl Bianca, the cute butterfly girl Vanessa, the aloof ice mermaid, and others - Joe gradually unlocks multiple attribute beast girls and confronts golden enemies.
