In this world, magic is in abundance where it is refined and mastered by its users. However, 3 families reign over and dominate the magical field, the Azure family (water), the Arashi family (wind) and the Ardiente family (fire). These major families decided to put the heirs of together, where they hope that they would unite the great powers in the coming future. This story revolves around Flare, a young child of the main branch in the Ardiente family, despite his young age his life was strict with training and lessons to help him become a powerful mage able to fill his father's shoes as the head of the family but he still makes time to play with children in the orphanage nearby. However, on one fateful day, a cult of terrorists planned to wipe out the ardiente family with dark magic that was foolishly used . Destruction found its way to Flare as he sees his clan being massacred by beasts and terrorists alike, all he could do was search for the one's important to him, his family. On that day, fate was cruel to Flare as his mother was slaughtered right in front of him. Now seeing his sister, Brennen, on the ground helpless with the tip of a sword to her throat...everything started to fade away as time stopped and all he could here was a strange ominous melody. Then, something clicked in young Flare's mind. "You can save her you know, just lend me your body and i will give you the power you so desire...you don't want her to die...do you?"
"...No."
In the epic conclusion to the Devil's Deal series, Freya has one final chance to discover the full potential of her own power, and to use it to restore balance in the universe - once and for all. After the destruction caused by Roisin, Ferya and Torix come to terms with their losses and mistakes... And prepare for a final battle that will change everything.