The Lich’s Leverage by Safia Nyx

The seer said my fated mate is already dead.

Heather
I’ve dealt with plenty of scary prisoners, but this time is different. I’ve been assigned a lich. One of the rarest and deadliest monsters. He feeds on living energy and can kill with a touch. In prison, he’ll only be fed rats, so he’ll be very hungry for the energy of living things. And I’ll be alone in a room with him.
This time my anxiety could be right. I might not make it out alive. I wouldn’t be the first person he’s killed.

Vedrac
I’ve endured a century of being dead. My soul locked away, my body imbued with the traits of a snake by the ritual that granted me immortality and magic. I thought I was ready to embrace a true death. But in my meditations, I glimpse a storm of beautiful energy. Something I never thought I’d find. A mate.
Now, I have a reason to live. Even if she never wants me, I’ve sworn to protect her. And her greatest enemy is one to be feared. Herself.

Fated Inmates is a series of novellas about morally grey monsters with dark pasts and the human women they are fated to claim. Each book can be read alone, but they happen in the same time frame, in the same prison. So you will get the best experience if you read them all in order.