Koshiro, usually referred to as Yakuma or Yakuma-sama (meaning Doctor Yakuma), is a highly skilled, level headed and creative doctor. He appears to be very young for someone so well trained (a bit like Utsuho). Yakuma can perform surgery though (being in Old World Japan) it is not a publicly embraced form of medical treatment. No wound or request can phase his iron will to serve. Yakuma claims he can "cure anything but foolishness." He, Utsuho and Pochi met because Yakuma was in a town to heal the local lord; Utsuho and Pochi were wandering through town and were driven into an inn (due to vandals and a wounded man) where Yakuma is staying. Yakuma thinks trust and honor are even more important than curing a sick person and refuses to put them to sleep and cure them without their permission. He can take people of any size or shape down using skilled delivery of pressured blows. His favorite battle strategy is rushing blindly forward instead of using stealth. Koshiro says he hates all itsuwaribito more than anything, but seems to accept Utsuho after hearing how he uses his lies; he, however, claims he will live righteously. Yakuma is a good person who will sacrifice anything for a patient in need. As an example, to save the village lord, he cut his own stomach open (in a way that would not kill him) because an itsuwaribito boss told him to or he would kill the lord. This ended up proving to the lord Koshiro was a trustworthy doctor.
(, First impressions)