Luo, a moss-removing boy with an unfortunate past, and a masked girl called the "Child of Calamity," who was confined to a ruined castle. The two meet by chance, part ways, and then fatefully reunite. A journey of trials to save the world from destruction. What awaits them is unavoidable despair, or an impossible miracle? A classic and orthodox boy-meets-girl story. A fantasy of love and adventure in another world.