Asta's demon form in Black Clover is a sight to behold: Red-eyed, half-black hair, horn emerging from one side of his head, two elongated canines, and a black wing sprouting from his back all combine to create the perfect demonic look. He also possesses a five-leafed grimoire, which is known to harbor an entity named Liebe. When Asta needs more power, he comes face-to-face with the devil.
Source：https://www.cbr.com/black-clover-asta-demon-forms-most-powerful-techniques/
