Kazuki Ohdouji, the eldest son of the wealthy Ohdouji family, finds his path to academic success blocked by a nightly recurring spectacle—the crude sexual acts of his parents. His mother, endlessly chasing feminine pleasure, writhes in ecstasy, her body captivating Kazuki's gaze and driving him into a daily cycle of masturbation. But one night, she deliberately takes his virginity, plunging them both into forbidden desire. As a result, he ends up impregnating his mother. Behind this act lie the traditions of an old family and the inescapable fate of blood ties—something no one speaks of, yet something that quietly, undeniably, controls his life.