A male high school student, habitually pursued by girls but determined to avoid impure relationships, learns a shocking truth from his mother: he is an incubus, a demon that must consume female energy to survive. As his body begins to suffer from the untapped hunger, he realizes the danger is real. Desperate to live without compromising his ideals, he makes a calculated decision. After school, he calls his teacher into an empty classroom and proposes a purely physical arrangement framed as a life-saving measure—no romance, just aid. When he touches her, the incubus power jolts through him, and she responds with an involuntary shiver. With her consent, he begins feeding on her energy, but the relationship quickly grows more complicated than a simple transaction.

Set against a contemporary Japanese school backdrop, the story follows the protagonist, whose name is given as Ichijiku, as he navigates his dual nature. His teacher, Ms. Shinonome, becomes both his lifeline and an unexpected object of genuine affection. Over the course of the narrative, Ichijiku wrestles with the contradiction between his incubus instincts and his longing for pure, emotional love. The series balances erotic tension with heartfelt character development, exploring themes of identity, consent, and the search for authentic connection in a supernatural framework.

As the story progresses, additional characters and situations test his resolve, and he must decide whether he can satisfy his demonic needs without losing the possibility of a real, loving relationship. The narrative arcs include the initial revelation and reluctant partnership, the gradual deepening of the bond between Ichijiku and his teacher, and the broader challenge of maintaining his humanity while embracing his incubus heritage.