Summary Nina is Plotting My Death! from Kainu Manga
Nina is Plotting My Death! summary: Reiji Takahashi is a secret agent of the Interior Ministry who found a little girl during a mission. The girl Nina was trained by the mafia to be a cold-blooded killing machine. Now Reiji has been ordered to watch over Nina, and he better watch his back, too, because Nina is still out to get him! A hard-boiled child-care comedy remake from a popular SNS work.