Nishikida Keibu wa Dorobou ga Osuki

Jack the Phantom Thief travels the world stealing extravagant treasures, but the most outrageous thing he's stolen was something he never wanted in the first place: the heart of the eccentric Inspector Nishikida, who's in charge of capturing him. Jack, whose real name is Anri, joins the police force to gain access to inside information, and hijinks ensue between the two of them both on and off the job.