Opal / Jennifer Armentrout.

No one is like Daemon Black. When he set out to prove his feelings for Katy, he wasn't fooling around. Doubting him isn't something she'll do again and now that they've made it through the rough patches, well, there's a lot of spontaneous combustion going on. But even he can't protect his family from the danger of trying to free those they loved. With help coming from the most unlikely source and Adam's death still lingering with those who loved him, friends will become the deadliest of enemies and the villains will no longer be clear. When each step they take in discovering the truth puts them in the path of the secret organization responsible torturing and testing hybrids, the more Katy realizes there is no end to what she's capable of. They won't turn back, even if the outcome will shatter their worlds forever.