Sousei no Onmyouji Manga

A brief description of the manga Sousei no Onmyouji:

Since ancient times, the valiant Ommyoji have fought against the evil spirits born of human fear, pain and despair. Since childhood Rokuro dreamed of becoming the strongest Ommyoji and of clearing the world of Pitfish, but the terrible tragedy for many years has killed in him any desire to fight. But who cares about the desires of a hyperactive boy, when the fate of the whole world depends on him and the talented girl Benio?