Flux - The Sunless World, #2

Actress. Businesswoman. Trend-setter. Before she was all these, Sable Monarique was the timid, awkward daughter of a disgraced family. After leaving home and crossing the Divide, she reinvented herself in Oakhaven. But now it's time to return. Her friend Rafe is a mage newly come into his powers and in desperate need of training. Sable brings him to the domed city of Monaria, with its giant trees, massive platforms, and impressive magic.
While he studies, she works to rebuild her family's fortunes. But Sable's not the only one who changed in the last seven years. New families have risen to prominence. An old flame isn't the man she loved and left. And now a conspiracy threatens to tear her city apart. Sable needs answers fast-before it's too late to save Monaria.