Asumu Ushiromiya

Rudolf’s first wife and Battler’s mother. She was an especially kind individual, with Rudolf choosing her over Kyrie because she accepted him for who he was despite his flaws and would forgive his mistakes.It is revealed in Alliance of the Golden Witch that she is not Battler’s biological mother.When Rudolf got both Kyrie, and Asumu pregnant at the same time, Asumu's child ended up being stillborn, and Kyrie gave birth to Battler. Rudolf then switched Battler with the stillborn child, and deceived everyone, including Kyrie into believing that Battler was Asumu's child.In Last Note of the Golden Witch, Asumu Ushiromiya is revealed to be Piece, the Witch of the Piece, sent as an assassin by Featherine Augustus Aurora to challenge Battler, Ange, and Beatrice to a game to determine her identity,