Bumbling Doshin

(from ebookjapan):
Kurari Yumnosuke , a carefree and self-indulgent bureaucrat, is a "bumbling doshin" (a doshin is a class of constable in the Edo era). On his haori is a ? mark. As he does not work, his son, Sorataro, deduces and solves difficult cases. At the climax of a case, the mysterious "throwing sesame hood" appears out of nowhere and plays a major role! A bright and unique detective story.