The subversion of the story is that "the saint's waste is just a disguise." The heroine was born with the supreme physique of "compatibility with all beasts", but due to a certain seal, she was unable to cultivate spiritual power, and was misjudged by the outside world as a useless spiritual root. When the humiliation of breaking off the engagement activated the blood of the ancient gods in her body, what she awakened was not spiritual power, but the "Sacred Code of Beast Control" that signed a soul contract with all the beasts in the world. She doesn't need to practice on her own, the source of her power is the monster she contracted with. When others break off the engagement, it is a slap in the face; when she breaks off the engagement, she releases the beast in the cage.
