In a shadowy modern metropolis torn apart by bitter division between humans and shadow beasts, Len, a gentle human physician with a gift for healing hidden magical wounds, stumbles upon Kael, the powerful cursed sovereign of the shadow clans. Gravely wounded and on the brink of collapse, Kael binds them to an ancient, irreversible life sigil—their fates now intertwined; if one falls, the other perishes.
Len fears Kael’s dark, corrupted magic and feathered infernal form, while Kael distrusts humanity’s long-standing hatred of his kind. Yet forced to stay side by side, they slowly peel back each other’s barriers. Len eases the agonizing golden curse cracks spreading across Kael’s skin with his rare light magic, and Kael shields Len from violent anti-beast fanatics lurking in the city’s skyscraper shadows.
A malicious faction stirs chaos, plotting to exploit their shared sigil to spark a full-scale race war, hoping to eliminate both species’ leaders at once. As danger closes in, the bitter forced bond between the soft-spoken healer and the brooding dark lord blooms into forbidden devotion. Together, they must overcome centuries of prejudice, outwit ruthless conspirators, and reforge their cruel life sigil from a chain of captivity into a vow of eternal love, carving a fragile path toward peace between two worlds.
