To wrap-up the trilogy...
SAME SAME. Gabe, Jace and Ash sound the same. It's like the same person is talking only with different names. Even the females are the same. Most scenes are just repetitions, too.
I noticed that the main female characters in this series are "damsels in distress." They lacked accomplishments and self-worth maybe that's why being in a dominant-submissive relationship appealed to them. If they were successful kick-ass females, I don't think they will allow a dominant to rule their lives.
I don't get you BDSM. Can't people just have relationships without the label? Being the submissive or the dominant is not necessary in making relationships work. Sadism and masochism? Shouldn't that be illegal? Even if the act is consensual, what if they start slicing each others' flesh? I don't think that two persons can be so in tuned with each other that they'll know just how much pain the other can take thereby inflicting just the right amount of pain.