An incident occurred in Akebono City where various things were gnawed. People begin to fear at the sight of ancient demon creatures flying in the sky. But, Kenji had a more frightening cause of worry. It is said that his older sister who is scarier than the demon coming for a visit. If he doesn't show his older sister how well he is doing in town, he'll be taken back to the countryside. Kenji, who doesn't reveal that he is RyuKenDo, falls into a pinch. With flying demons appearing here and there, his older sister finally came to town!
Umi Saionji chega a cidade de Akebono e estava anciosa para ver como Kenji tem se saindo enfrentando os monstros da Yamanga, mas ela descobre que a polícia e até o próprio Kenji não enfrenta os monstros e Umi decide levar Kenji para sua terra natal e revela que é a prometida de Kenji. Durante a luta dos monstros aéreos da Yamanga, ela vê Ryukendo e reconhece seu estilo de luta usado por Ryukendo, Umi descobre que Kenji na verdade é Ryukendo.
