Kyou is a bad-mouthed and aggressive girl who is also well known as a good cook. She is the older of the Fujibayashi twins. She was in Tomoya's class in their second year, and has maintained a steady friendship with Tomoya even though they are put in different classes on their third year. She is currently the class representative of her class. She has a pet baby boar named Button (ボタン, Botan?). She even has her own motorbike (in this case a scooter), which is known only to Tomoya and her sister, as Kyou does not want the news of her possession of it to be known, as she fears suspension from school because she is not allowed to ride a motorbike to school. Her favorite weapon is various types of dictionaries, which are thrown at anyone she gets furious with, typically Youhei. In the anime, Kyou uses various books as weapons more often, and while Tomoya almost always avoids them, Youhei gets hit almost every single time.
Kyou's story starts when she tries to make Tomoya get intimately close with Ryou, thus becoming their cupid angel. After a rumor about Tomoya being two timer with Ryou and Kyou, Kyou starts avoiding Tomoya, Ryou becomes more bold. Youhei finds out that Kyou has a crush on Tomoya too, and advises Tomoya to settle things out before more misunderstanding happens. After much conflict of playing boyfriend and girlfriend with Ryou, Tomoya breaks up with Ryou and confesses his love to Kyou, in return confesses her love to him and become boyfriend and girlfriend. When autumn arrives, Ryou finds herself a new boyfriend, which is strongly hinted to be Kappei.
Kyou works as a kindergarten teacher in the After Story portion, and coincidentally is also Ushio's teacher. According to Tomoya, her personality is still the same even after reunion, but Ushio says that Kyou is a good teacher.
In the movie, Kyou doesn't talk to Tomoya as much as in the anime. Her relationship with Tomoyo is also better than the one in the anime.