The Night Realm by Annette Marie

Clio isn’t a thief. She isn’t a spy, a soldier, or a diplomat. Aside from her rare ability to mimic spells, her only notable talent is gardening.

But with a war threatening her homeland, and her half-brother—the nymph prince—pleading for her help, she agrees to attempt the impossible: stealing deadly magic from the best spell weavers in the three realms.
Their stronghold is located deep in the Underworld, which is exactly the sort of place an Overworld nymph like her should never go. Getting in won’t be that hard. Getting out alive is the impossible part.
Lyre is a master of two skills: spell weaving and seduction. As an incubus, he can enthrall any woman he desires. As a master weaver, he can create any spell imaginable—but not the spells of death and destruction that his ruthless family specializes in.
A master weaver who can’t—or won’t—contribute to the family legacy is a liability that won’t be tolerated for much longer. And when a nosy Overworld nymph starts probing into his secrets and draws the attention of his sadistic brothers, his odds of survival take a nosedive.
Because some magic was never meant to be woven. And while Lyre’s most dangerous creation could be powerful enough to save Clio’s homeland, it’s terrible enough to destroy far more.
And neither Clio’s mimic ability nor Lyre’s spell weaving will save them from its power.

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Celebrating the 10th Anniversary of the best-selling Steel & Stone series, the second edition of The Night Realm features a revised story and new cover.

Note: The Spell Weaver and Steel & Stone series are set in the same world but can be read independently.