Once upon a time, a young forest princess became friends with a lonely demon boy. He gifted her a ring, a worthless trinket - or so he thought. Because no sooner did he slide it onto her finger than the demon queen and forest king declared war. Years later, Cassia is a crucial force in her fathers army, wielding her ring of light against hundreds of demons at a time. Then battle-hardened Zeru abducts her, planning to back steal the ring to fix his childhood mistake. Terrified, and more than a little mistrusting, Cassia is forced to travel with Zeru to a place they both believed only existed in storybooks, one where their friendship slowly rekindles into something much more. But its only a matter of time before the war theyve escaped comes for them, and a hidden threat to forest folk and demon alike grows in the shadows.