The Amaranthine Complete Series. The Amaranthine Chronicles

Blood flows where magic fears to tread. For centuries, the city of Ormere has existed on a knife's edge. A band of outlaws known as the Amaranthine has kept the peace while the Order of Sorcerers disperses their dark magic amongst the city's people. But Agent Kaylan Avilion won't stand for it. Still dealing with the grief over her murdered family, it's up to Kaylan to protect the city she loves. But when an attempted sting on a criminal sorcerer goes bad, Kaylan's fiancé Elijah pays the tragic consequences.
Kaylan's overwhelming sorrow is replaced by shock when she realises Elijah isn't really dead. He's alive and under the spell of the Order of Sorcerers, and they won't rest until they find a dangerous artefact that holds the key to Kaylan's tragic past. When her sister Freya goes missing, Kaylan pulls out all the stops to find her and Elijah. But Elijah has been keeping a secret from Kaylan, and it just may be enough to tear them apart.
again.