The fate of the world rests on Suzume's shoulders—if she doesn't set it ablaze first.

Suzume can't control her fire magic, especially around Kaito, whose flirtatious taunts are driving her to distraction. There's no time for romantic entanglements, not when she keeps bursting into flames. She needs to learn control and quick, before the immortal maniac hunting her catches up. Then a chance meeting leads her to a mysterious stranger whose power balances her and puts control in her hands.

Kaito's magic is already a mere shadow of its former glory, when a priest turns him mortal by accident. In the past he would've claimed vengeance in blood, but Suzume begs for the priest's life. He shows mercy, despite lingering doubts. To replenish his water magic, he must seek the mysterious Sea Stone, whose water magic can heal him. Their journey is perilous, and demands an increasing toll on Kaito, while Suzume's power seems to get stronger by the day.

While Suzume's magic rises, Kaito's wanes. And the stronger she gets, the louder Kazue's voice in her mind becomes, tempting her with power beyond her imagination; if she's willing to let everything burn. To defeat the darkness, she needs her fire, but by nature fire consumes, and if she lets it burn out of control for too long, it will devour her and Kaito both.