The Iron Witch Series by Karen Mahoney

Freak. That's what her classmates call seventeen-year-old Donna Underwood. When she was seven, a horrific fey attack killed her father and drove her mother mad. Donna's own nearly fatal injuries from the assault were fixed by magic—the iron tattoos branding her hands and arms. The child of alchemists, Donna feels cursed by the magical heritage that destroyed her parents and any chance she had for a normal life... moreFreak. That's what her classmates call seventeen-year-old Donna Underwood. When she was seven, a horrific fey attack killed her father and drove her mother mad. Donna's own nearly fatal injuries from the assault were fixed by magic—the iron tattoos branding her hands and arms. The child of alchemists, Donna feels cursed by the magical heritage that destroyed her parents and any chance she had for a normal life. The only thing that keeps her sane and grounded is her relationship with her best friend, Navin Sharma. When the darkest outcasts of Faerie—the vicious wood elves—abduct Navin, Donna finally has to accept her role in the centuries old war between the humans and the fey. Assisted by Xan, a gorgeous half-fey dropout with secrets of his own, Donna races to save her friend—even if it means betraying everything her parents and the alchemist community fought to the death to protect. less

Donna Underwood is in deep trouble.An ancient alchemical order is holding her accountable for destroying the last precious drops of the elixar of life. Never mind the fact that Donna was acting to free her friend, Navin, from the dangerous clutches of the Wood Queen at the time. But what the alchemists have in store is nothing compared to the wrath of the fey. The Wood Queen has been tricked and Donna must pay. Get ready for all hell - quite literally - to break loose...

After being tricked into opening the doorway to the Demon Realm by Aliette, the Wood Queen, Donna Underwood is faced with a terrible ultimatum from the newly released demon hordes. They demand that the alchemists deliver the Philosopher's Stone, or their reaper storm will plunge the world into a devastating modern-day Dark Age. Donna is sent to London, England, where she must complete her alchemist's training and learn how to recreate the Stone. But time is running out... moreAfter being tricked into opening the doorway to the Demon Realm by Aliette, the Wood Queen, Donna Underwood is faced with a terrible ultimatum from the newly released demon hordes. They demand that the alchemists deliver the Philosopher's Stone, or their reaper storm will plunge the world into a devastating modern-day Dark Age. Donna is sent to London, England, where she must complete her alchemist's training and learn how to recreate the Stone. But time is running out. Between facing the vengeful demon king, Demian, and collecting the Stone's elements, Donna realizes she must give her own life in order to succeed. And this time, even braving death may not be enough to save the world. less