The main character, Tomohiro Kutsuki, was summoned into the world of Eunifonia by two beautiful persons, Alice and Freya, as a hero who can help save the world. Well, how can an avid otaku Tomohiro help, you ask? What is its peculiarity? And the fact that his sperm is capable of increasing magical powers! And the first task on the way of our protagonist and six beautiful companions is to snatch the kingdom of Ephonius from the hands of the Magic Four.