Prince Pixel of the Canvas Kingdom stumbles onto the seal of an ancient Devil while skipping his studies. He picks up the graffiti wand that Pastel, the seal's guardian, uses to maintain it — and breaks the seal, freeing the Devil. Charged by Pastel with undoing what he caused, Pixel fights his way through the kingdom's worlds alongside Tablet, the Devil's son, who both helps and challenges him. He defeats Tablet's sister Palette, rescues Pastel, and confronts the Devil directly — only for Tablet to steal Pixel's wand and destroy his father himself, declaring himself the new Devil. Pixel defeats Tablet too, uses the wand to create a new body for him, and then refuses to let Pastel re-seal the Devil, which would trap her alongside him. The Devil escapes weakened; in exchange, he begins restoring what was lost to the kingdom.