Don’t Call it Mystery (Omnibus), book 01
Yumi Tamura2018

Totonou is a young college student who stands out—both for his bushy hairdo and his finely-honed abilities of observation and deduction. When Totonou is accused of murder, he puts his skills to work and uses his exceptional insights to find the real killer. Later, all Totonou wants to do is return to his own little world, but he can’t avoid getting caught up in one mystery after another. In his own blunt yet gentle way, Totonou is a truth seeker who tries to make sense of a chaotic—and often dangerous—world.