A Campione – a Godslayer – is a supreme ruler. Since he can kill a celestial being, he can call on the sacrosanct, divine powers wielded by the gods. A Campione – a Godslayer – is a lord. Since the power to kill a deity is in his hands, he therefore looms over all mortals on Earth. A Campione – a Godslayer – is a devil. Of all mortals who live in the world, none can assume a power to match his!
Kusanagi Godou is a 16-year-old boy who played catcher and fourth hitter in senior league baseball until an injury put an end to it in junior high. As the spring break of his third and last year of junior high came around, he got involved in an adventure and ended up slaying one of the Heretic Gods, Verethragna. Thus, he became the youngest - and seventh - Campione. Now that he is a Campione, a god slayer, young Godou must defeat the troublemaking gods with the help of his followers.