What is the the book the Van Alen Legacy by Melissa de la cruz about?

The Van Alen Legacy is the 4th book in the Blue Bloods series by Melissa De La Cruz.

Schuyler and Oliver have fled the Committee by travelling all over the world. Mimi has joined with the Conclave to find Jordan Llewellyn, and Bliss is inhabited by a "Visitor".

The books themes are mainly: the broken bonds of Jack and Mimi, vampires, demons (kind of...), and choosing between 2 loves