K-9

K-9, officially Marine Ninth Penitentiary (海軍 第9 刑務所, Kaigun Dai-Roku Keimusho), is a Prison located in the. It is most notably run by an all- guard unit.

Behind the Scenes
The short-hand notion for this penitentiary, K-9, is a homophone for canine, which references its all-Mink personnel.