Behold, a great detective who thrills the world solving impossible cases in no time! His name? Keiichiro Nagumo. …But all of that was over a decade ago. Now he's just your typical middle-aged dude. Nagumo is behind the times to the point that he doesn't even know what a smartphone is. But out of the blue, he is confronted by a high school girl named Mashiro who shows up wanting to be his assistant. Witness the miracles a gender-gap detective duo can make! 
 
(Source: One Peace Books)

Nagumo Keiichirou was a genius high-school detective. No case was complex enough for him. But what happens to genius detectives when they get older? 
 
Now 35, with bad hips, running a failing detective agency with no cases to solve and struggling to pay the rent, he's at a dead end. 
 
In comes a high school girl in his office who says she wants to work with him. With her help, will the out-of-touch, old-fashioned Nagumo get back the fire of his youth?

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