Stone Under Skin by BL Maxwell

Ankit has lived many lifetimes. Once, long ago, he was made of stone, and marked with symbols and sigils meant to safeguard him and allow him to protect and serve others. He’s a living gargoyle now, cursed to live as a human; always watching, at all times aware, and constantly searching for his fated one.
While walking home from his job as a librarian, Ethan Lewis is beaten and robbed. Ankit stumbles upon him, and instantly recognizes him as the man he’s fated to. He helps him back to his apartment, and after tending his injuries, watches over him.
Fate has woven their lives together for centuries, but in every lifetime, they could never live freely, or love each other as Ankit has often dreamed of. To change their destiny, they’ll fight together with other gargoyles, and a young watcher, who is unaware of the tremendous power she possesses. This will be the last battle against their creator, and they’ll either die fighting for their freedom, or survive to live the life they’ve always yearned for.