Toru Odamori dies in a bus crash on a school trip and wakes reincarnated in another world with the job of a slavemancer, able to bind people to his will by force. He starts using it, and word of what he is doing brings Kirika, a princess knight sworn to Princess Sistina of the kingdom of Lambardia, out to stop him. Kirika turns out to be the reincarnation of Kirika Himeno, the class representative who barely noticed him back home, and Toru sets about building a harem around her.