Deception by Alexia C. Praks

One girl with a unique ability. Gorgeous men with supernatural powers. Demons roaming the streets at night. A dark mystery. What could go wrong?
Daniella Romano is a rookie blood Alchemist, an individual who has the ability to transmute blood into powerful weapons, and she wants blood revenge.
Zach and Connor Hasting are noblessen (individuals with unique magical power), veteran blood alchemists, and notorious master strategists. They’re determined to find out who framed their father in the case of treason.
Saito Ren and Shin are blood alchemists and Daniella’s best friends. Ren is investigating a series of gruesome murders done by a new type of demonic creatures they have never seen before. Working under the Shadow, he must figure out what these beings are before more lives are lost.
When seventeen-year-old Daniella masquerades as the son of a low-ranked Chinese lord, and waltzes with her comrades into the earl of Middlemarch’s birthday party in order to assassinate a high demon, her revenge plans turn sour. There, Daniella meets Zach—a Greek god if she ever saw one—who suspects she is an imposter and will not let her escape his sight. Amidst the exuberant atmosphere, a man shoots the powerful king of Darnia; meanwhile Daniella witnesses another influential lord slaying the culprit, and her friends are captured, ultimately becoming the prime suspects in the case of treason.
Now, it is up to Daniella and the Hasting and Saito brothers, along with the Master of Disguise Coterie, a team of eccentric actors, to work together to get to the bottom of the deadly mystery.