The story is about some cases happening in the school and the town the MC lives.
The MC is the usual timid normal guy you find in a billion manga about detective work...PSYCHE, that is how the first couple chapters make us believe, MC is in reality a goddamn genius, he realizes cases are happening, the culprit, the motive and how to revel the truth, it seems like he doesn't want the attention or wish to be the involuntary assistant and fakes being inept and sometimes makes incidents that make the female lead brain gears work, she is smart and capable, but he is better, from what I've "read" they are almost even, the girl thinks that the way his random actions produce the best ending is strange and is trying to remove his facade, but MC doesn't surrender and tricked her a few times.
When I say he is smart I mean it, many moves he does have a butterfly effect pages later that aren't a random casuality, he planned it in case something had gone wrong, sometime before starting the plan and sometime on the spot, as Batman his backup plans have backup plans.
It looks like he produced a second personality that acts as the clumsy student because he would be unable to act all the time but directs his sub actions and "emerges" with a hand habit he can produce at anytime and take full control, he gone the extra mile for it.
When a detective gets called for a incident or trips on it when is happening or after the MC actually check the situation around him and make so to direct the girl there, he could avoid some stuff to entirely happen at times but as it would mean he gets the spotlight he refuses it and let it happen.
Re-reading a certain chapter makes me believe that he got bored with the world as he had studied everything there was to study and following a certain incident where he have seen a "criminal" break in pieces after being found out discovered he loves to see bad people collapse, no idea why he doesn't want to be the one to do the reveal.
He is a bit Kira and L, good and twisted.