The story of Yondemasuyo, Azazel-san. - originally a supernatural gag comedy manga authored by Yasuhisa Kubo - revolves around the detective Akutabe, his assistant Rinko Sakuma, and the various magical demons that Akutaba uses for his cases - including the titular Azazel. The OVA version is adapted by Production I.G, and it's being bundled with limited edition volumes of the manga.