Furachi na Keiji-Sanふらちな刑事さん; The Bawdy Policeman

A detective, Takeda Issei, for the sake of destroying a yakuza group, surrenders his body to a yakuza member, Ishii Suguru, in order to obtain insider information. Even though Takeda has a rule where “I refuse to have a lover or a special person,“ the reason Ishii becomes his lover is――.