Clannad is set in a high-school located in some Japanese town. Okazaki Tomoya is a third-year student who doesn't take his studies seriously. Always late for class, he's seen as a delinquent by the rest of his classmates who are busy preparing for their entrance examinations. Needless to say, he hasn't too many close friends either. Tomoya seems not to mind too - until one day he meets a girl, Furukawa Nagi...