Angellus is the celestial realm of guardian angels, while the demons dwell in Dibérnia; their ancient war over human souls on the world of Martel ended when the angel Einglenn sacrificed immortality to erect a barrier between realms. When Cello, a renowned guardian, alters a human’s lifeline out of love—a forbidden act—he is exiled as a fallen angel. Luminus, seeking to understand human emotions and his friend’s choice, escapes Angellus to pursue the meaning of love, setting events in motion that may alter the fate of all worlds.

Angellus is the celestial realm of guardian angels, while the demons dwell in Dibérnia; their ancient war over human souls on the world of Martel ended when the angel Einglenn sacrificed immortality to erect a barrier between realms. When Cello, a renowned guardian, alters a human’s lifeline out of love—a forbidden act—he is exiled as a fallen angel. Luminus, seeking to understand human emotions and his friend’s choice, escapes Angellus to pursue the meaning of love, setting events in motion that may alter the fate of all worlds.