Mephisto Pheles

Samael (サマエル Samaeru), better known by his alias Mephisto Pheles (メフィスト・フェレス Mefisuto Feresu) and publicly known as Johann Faust V (ヨハン·ファウスト五世 Yohan Fausuto Gosei), is one of the children of Satan, he is the second-strongest of the Eight Demon Kings holding the title of King of Time (時の王 Toki no Ō), and the older half-brother of Rin and Yukio Okumura.