In a world where heroes are always women chosen by the gods, the existence of a male hero is considered a myth. Cherio, a young man with an unabashed love for eroticism, stumbles into a battle between a female hero named Yuriel and a gang of monsters. As Yuriel struggles, a goddess intervenes and grants Cherio the power of the legendary male hero, giving him the unique ability to unsheathe the mythical Holy Sword—an act that carries unmistakably erotic overtones. By pulling the sword from female heroes, Cherio can unleash devastating power and turn the tide against the demonic threats that plague the land.

After this awakening, Cherio is formally inducted into the hero organization, where he is assigned to a squad alongside several female heroes. These include the capable and serious Lelia, the energetic and loyal Saran, and the fiercely determined Rosemary, who harbors a deep grudge against the demon lord's army. Through his interactions with each of them, Cherio unlocks their respective holy swords, strengthening their abilities while navigating comedic and risqué situations. The story balances raunchy humor with action-packed battles, as the group faces increasingly dangerous foes.

The narrative arcs unfold as Cherio undertakes his first official missions, proving his worth despite skepticism, and later confronts a sudden large-scale invasion by the demon lord's forces. As the invasion escalates, Rosemary unleashes her full power, and Cherio must risk everything to protect the people and the friends he has come to care about. The series blends ecchi comedy, fantasy adventure, and a harem dynamic, with Cherio’s perverted yet good-hearted nature driving both the humor and the emotional stakes.