Tōru Odamori dies when his class bus explodes on a school trip and wakes up reincarnated in another world with the power of a slavemancer, able to bind people to his will. He soon crosses paths with Kirika, a Princess Knight serving Princess Systina of Lambardia who turns out to be the reincarnation of his former class representative, Kirika Himeno. With his strange new ability, Tōru sets about gathering a harem around the proud knight who once barely noticed him.