Kawaguchi 【河口】5 The Japanese surnames etymology dictionary.
① There is a surname including "Kyo".
② Korean type . Originated in the county of Gyeongsangbuk-do, South Korea, Hoshuzu (aka: Kyoung-san) county. "Kyoyama is the main line" There is a record of naturalization on Nara-ken Sakurai-shi on July 26, 1988. The real name is Zhao. 趙 reference. There is mini in the real name. 閔 reference.