watch 01:50 The Loop (TV) Do you like this video? This article is about a/an character in Kamen Rider Ex-Aid. Seiichi Kuboyama (窪山 誠一, Kuboyama Seiichi) is the boyfriend of Yoko Horiuchi. Character History Behind the scenes Portrayal Seiichi Kuboyama is portrayed by Daiki Tsuji (辻 大樹, Tsuji Daiki). Retrieved from "https://kamenrider.fandom.com/wiki/Seiichi_Kuboyama?oldid=334329" Categories: Kamen Rider Ex-Aid Civilian Ex-Aid Characters Community content is available under CC-BY-SA unless otherwise noted.