Ryoku is a boy from Shin village, East Asia. He met Black Star as he and Tsubaki were looking for Masamune. It appears that Ryokou and/or his village has had dealings with the Star Clan in the past, as he recognized the tattoo on Black Star's arm, but he may just know that from the clan's reputation. At first believing Black Star was part of the Star Clan, he offers him money to leave before chasing him out of the village for fear he may attack them. However, it was that fear and the fear of not being powerful enough which allowed him to be possessed by Masamune. After Masamune was defeated, Ryoku comes to realize Black Star was not a member of the Star Clan but that still didn't mean that he liked him anymore than before.