Black Clover's newest arc has had Asta facing off directly against the devil inside of his grimmoire in order to form a better and stronger contract with it, but the newest chapter of the series really threw a major curve ball in there when it finally revealed the identity of Asta's mother. Ever since Nacht took him under his wing in order to strengthen his devil abilities for the upcoming rematch against the Spade Kingdom's Dark Triad, Asta (and fans of the series) have been learning more about the devil that has been in the grimmoire this whole time.