On a day off, the protagonist was once again being chided by his osananajimi Hikari for not pursuing a girl. He just wanted to spend his time enjoying his hobbies, and ran away from relationships by any means, due to his past trauma. She was worried that if this continued, then he would become completely useless.
Then suddenly a bright light enveloped them and they were transported to another world. While they were still lost in their new surroundings, the prime minister Marrou told him that he was the ‘last king’ of the kingdom. He was loved by the people, but he must abide by the duty of building a harem to father his future descendants for the prosperity of the kingdom. In fact, it had already been arranged that the princess Sophia from the neighbouring kingdom and Charlone, the beautiful daughter of a noble family, will be part of this harem. Seeing him surrounded by girls, Hikari could not hold back as well, to his dismay.