Action Adventure During the Tokugawa Shogunate

Taking a break from the fourth Dunwich Committee on Student Safety story and trying to make a submission deadline with an action-adventure tale set in Japan during the Tokugawa Shogunate:

After two young children witness a brutal murder by a powerful gang, a komusō (wandering mendicate Zen monks known for wearing reed hoods and playing bamboo flutes) tries to see them safely through a dangerous forest to the Shrine at Nakazama for a secret rendezvous with the local magistrate and his men.