Eldritch (The Eating Woods, #2) by Keri Lake

In the grimly captivating sequel to Anathema, Maevyth and Zevander must navigate the perilous mortal lands to deliver Zevander from the clutches of an ancient, malevolent power that threatens to shatter both worlds.

An eldritch magic has awakened, turning the mortal world darker. Colder. Famished. With flesh-eating monsters and a sinister curse spreading like a plague, the last glimmer of humanity in Foxglove Parish has long-since faded.

For Maevyth and Zevander, the only chance of escape is through The Eating Woods. But fate has woven a new web, tangling the threads of destiny, and crossing the mystical boundary to Aethyria might not be so simple.

As the bones of Maevyth’s past are unearthed, and truths unravel with unsettling clarity, the possibility of never leaving Mortasia is becoming more of a reality. Unfortunately for Zevander, time is running out. The longer he stays in the mortal lands, deprived of essential vivicantem, the more he succumbs to the encroaching specter of madness.

Or maybe those chasing shadows are someone hunting him. A wretched evil closing in, threatening to pull him into the darkest corners of his mind.

Only, this time, Maevyth may not have the power to save him.