Lucifer

Lucifer (ルシフェル Rushiferu) is one of the children of Satan, he is the strongest of the Eight Demon Kings holding the title of King of Light (光の王 Hikari no Ō), and the oldest half-brother of Rin and Yukio Okumura. He is the Commander-in-Chief of the Illuminati. Frustrated by his continued inability to maintain a host in Assiah, Lucifer created the Illuminati with the intention of merging Assiah and Gehenna into one realm.