Unknown (Outcast Season, #2)

"...Living among mortals, Cassiel has begun to develop a reluctant affection for them--especially the intriguing Warden Luis Rocha. As the mystery deepens around the kidnapping of innocent Warden children, Cassiel and Luis are the only ones who can investigate within both the human and Djinn realms. But the more Luis and Cassiel search, the more dangerous the trail becomes, reaching not only into a fanatical splinter group, but into the highest ranks of Cassiel's immortal kin. An outcast from her own kind, Cassiel must now rely on her own limited earthbound powers to save the young Wardens...if it's not already too late."--p.[4] of cover.