Yondemasu yo, Azazel-san.
Japanese title: よんでますよ、アザゼルさん。
Type: OVA
Episodes: 4
Source: Manga
Genres: Comedy, Supernatural
Studios: Production I.G
Producers: Fonishia
Duration: 21 min per ep
Rating: R+ - Mild Nudity

The great detective Akutabe has an assistant, Rinko Sakuma, who is trying to learn to summon demons. This is the story of her misadventure when she actually manages to summon 2 demons unexpectedly.

(Source: ANN)