A Cornish witch who offers to cooperate with [Alex](https://anilist.co/character/89041/Alex-Rex) in investigating the murder of [Keyman](https://anilist.co/character/318499/Keyman). Her magic utilizes the powers of the Double Helix World, allowing her to summon various fleshy appendages and familiars, as well as transform her appearance into a more mature-looking one. Due to her considerable seniority over the rest of the cast (as well as her vast knowledge on a number of topics), she has a habit of patronizing others and generally acting sassy and condescending.

Keyman is the resident hero of Rockville City, a place inhabited by both humans and animal people. In the years since his debut as a hero, crime has decreased significantly, which does not look all that great for the local police force. But one day, after he catches yet another group of criminals, Keyman is mysteriously murdered. Detective Alex and his police force are investigating the murder, and one of their major clues is the words "Dr. Necro," which were carved onto Keyman's body after his death. Their case gets even stranger when Alex unexpectedly meets "Dr. Necro", who appears to be a young girl, in a bar. What monster could be behind the murder of Keyman, and what does the childlike Dr. Necro have to do with it all? 
(Source: MangaHelpers)

A collection of bonus chapters for series serialized in Comic Ryu, as well as interviews with their authors.
 
Contains: 
1. Neko Musume Michikusa Nikki: Oumisoka-hen (ねこむすめ道草日記・大晦日編) [Ike] 
2. Centaur no Nayami: Ningyo-hen (セントールの悩み・人魚編) [Kei Murayama] 
3. KEYMAN: Fuyu no Tokubetsu-hen (KEYMAN・冬のとくべつ編) [Warainaku] 
4. Maromaro: Kasa Jizou-hen (マロマロ・笠地蔵編) [Rakuraku]