After getting Natsuki hurt when a small dog barks at them, Ryoku gets depressed while questioning himself if he is useless. Moping by himself, Ryoku finds a partitioning screen in Natsuki's house with a powerful dragon and tiger on it. According to Natsuki's grandfather, the dragon and tiger are said to be rivals in the position of being the strongest animal. With the determination of becoming a powerful dragon, Ryoku begins to train.