Ryou is Tomoya's classmate and class representative. She is the younger of the Fujibayashi twins. Unlike her older sister, she is timid and doesn’t cook well (but is otherwise good at chores). Ryou is very keen about fortune telling, but her predictions, while incredibly specific, always manage to be either somewhat skewed or extremely wrong. Ryou plays as a major supporting character in both Kyou's path and Kappei's path.
Ryou has a crush on Tomoya, as shown in Kyou's arc, and needs Kyou's help on pursuing Tomoya. In Kappei's arc, she pursues Kappei instead, which worries Kyou. Ryou has her own optional path, where Tomoya pursues Ryou and become boyfriend and girlfriend, however it is considered as Kyou's bad end.
Ryou takes nursing course and most likely working as a nurse in After Story portion. Her job as a nurse is further proven as seen in Kappei's path five years later, where she works as a nurse, along with the anime adaption of Clannad After Story, where she is seen working as a nurse in episode 22.