The Dark SealThe dark seal of the sleeve, The dark seal the rebellion of the heavens

This is the story of Kiyo, a normal child who lost his father when he was a child due to a strange accident. In the present, Kiyo remembers the day they killed his father, he remembered that it was a demon that killed him, and with the help of a friend from his childhood, he begins the path of becoming the best exorcist to avenge his father.