Keeping It Real by Justina Robson

The Quantum Bomb of 2015 changed everything. The fabric that kept the universe's different dimensions apart was torn and now, six years later, the people of earth exist in uneasy company with the inhabitants of, amongst others, the elfin, elemental, and demonic realms. Magic is real and can be even more dangerous than technology. Elves are exotic, erotic, dangerous, and really bored with the constant Lord of the Rings references. Elementals are a law unto themselves and demons are best left well to themselves.

Special agent Lila Black used to be pretty, but now she's not so sure. Her body is more than half restless carbon and metal alloy machinery, a machine she's barely in control of. It goes into combat mode, enough weapons for a small army springing from within itself, at the merest provocation. As for her heart, well, ever since being drawn into a game by the elfin rockstar Zal (lead singer of The No Shows), who she's been assigned to protect, she's not even sure she can trust that any more either.