Oroka na Tenshi wa Akuma to Odoru

The story centers on Masatora Akutsu, a demon who descends to the human world in search of "idols" to motivate the corrupt demons and to boost their morale. He quickly finds a potential idol, Lily Amane, and recruits her. However, Lily turns out to be an angel, the natural enemy of Akutsu and the other demons! While Akutsu tries to corrupt Lily to protect himself and his clan, Lily decides to rehabilitate Akutsu for her own hidden ambitions. (Source: Crunchyroll)