Conan is the best friend of Benny Jack Bunnycorn. Although he acts dumb, Conan is actually pretty smart. He generally has better prediction skills than Fleet, and is also more cautious in situations. Conan often treats Benny to Chinese food at a restaurant known as the Golden Nekomata, but its never made clear where Conan works in order to make money. Conan generally drags around a clubaxe, a weapon that can be used as a bludgeon or a wedge.

Part of the reason that he acts dumb is due to a current brown law that forbids Oni from being smart. Conan has two brothers, a blue Oni named Arthur, and an orange Oni named Doyle, who remain hidden from the public due to this law. Conan, however, remains more open. He lives in an apartment building in Bluto City, the same city where Benny Bunnycorn lives.

(The three Onis of coarse make the name "Arthur Conan Doyle.")