Wicked Magic (Dark Sorcery #3)

Rhiannon Castle is a D'Anu witch whose  is a D'Anu witch whose Coven sisters know nothing of the Shadows that lurk within her. Rhiannon can't reveal the truth to anyone--least of all Keir, a rugged warrior soldier who walks into Rhiannon's life and awakens her to a wanton reckless desire…

Keir's Tuatha D'Danann Tuatha D'Danann  brethren are the only real family he has ever known. He trusts no one--until he is sent to San Francisco and meets Rhiannon, the one woman with fire enough to tame him. Every seductive encounter convinces Keir that she belongs with him--even though Rhiannon knows her powers could put him in peril…
 
And then a new threat rises from the depths of the Underworld. When a demon goddess unleashes her evil upon our world, Rhiannon's secret could prove the ultimate weapon in this epic battle--or forge a pathway to destruction for the only man she's ever loved…