The Chaos Circus — Renee Dugan

All Tessa LaRoche wants is to be the most ordinary person on Barrow Island. After a stint in a mental asylum, she's had quite enough of being anything else, thank you very much. But when a commission at her new reporting job forces her into the path of a not-quite-human murder suspect, Tessa finds that the unordinary is not through with her yet.

Spirited away by a devilishly charming Nicolai to the Mirror Lands-- a parallel reality manipulated by the immortal Deathless-- Tessa loses one of the most precious tethers to her sanity. In order to reclaim it, she must risk entering The Chaos Circus: a citywide fair where mortals trade years for prizes in vicious attractions from which the Deathless draw their power.

But there's a catch: if Tessa can't defeat the Deathless at their own freakish carnival games, she will lose her mind...and Nicolai will lose his life.

Forced to rely on one another despite the secrets that come between them, Tessa and Nicolai embark on a dangerous adventure through the deceptively beautiful life of the Circus, where little is as it seems--even the games, their pasts, and the strange whirlwind of memories that Tessa can no longer recall.