Also known as: 魔界探偵冥王星O
(まかいたんてい めいおうせい おー)
Light novel series written by different authors under the same pseudonym Echizen Matarou.
(Matarou is also a character in Asmik Ace's horror-comedy movie ’Neck’.)
Illustrated by Redjuice, Buriki, Hagure Keg and Tetsuo (Tashirosu).