A decade ago, monstrous entities known as "Aberrations" suddenly appeared across the world. Bearing striking resemblance to figures from ancient folklore and myths, they posed a dire threat to humanity. In response, nations assembled their finest warriors, scholars, and mystics—the Exorcists. Born into a prestigious exorcist family, Tōjūrō has spent his life fighting these beings. But deep down, he longs for a normal existence, away from the endless battles. That dream shatters when he encounters Behemoth, a legendary divine beast. Yet instead of a grotesque monster, he finds a breathtakingly beautiful woman who claims to be the true Behemoth. Tōjūrō’s mission is clear—eliminate all Aberrations. But when Behemoth offers an unthinkable proposal, his fate takes an unexpected turn… "I do not wish to destroy humanity. Instead… will you take me as your bride?" Thus begins a forbidden bond between an exorcist and a being he was sworn to slay—a tale of conflict, fate, and an unconventional love story beyond species.