Some people are haunted by their past. I'm hunted by mine. Maksim Smolov wasn't the monster I was running from. He's the devil I found. Those deep brown eyes didn't even blink. One minute, I'm being chased down a dark alleyway by the nastiest demons from my past; the next, they're begging for mercy from a man in an expensive suit. If I had known my savior was the most feared mafia boss in New York, I might not have repaid his kindness with a kiss—a kiss that led to the hottest night of my life—but I did, and that was that. A week later, I'm back fending for myself. So, when I hear my best friend is taking private self-defense classes, I beg to join her. It seems like a good idea... until I meet our teacher. My one-night stand. Turns out, he's her uncle. Tsar of the American underworld. Maksim Smolov. Just like that, I'm not sure what to be more afraid of: The demons from my past... or what this devil will do when he finds out about them. Unholy Tsar is a standalone dark mafia enemies-to-lovers age gap captive romance with mature themes and a happily ever after. It is the fourth book of the Ruthless Dynasty series.