Possibly the poorest written 'dark romance' I've read. 
Think sappy Bella/Anastasia. 21 Yr old virgin is kidnapped by Russian Mafia, then falls in love with the anti hero who accidentally rescues her. Suddenly falls in love, calling him daddy/sir by day 2, she has no interesting back story, he's a big tough ex mafia enforcer type but they can't live without each other. Too many plot holes and contradictions to make remotely believable. Sorry but I think 2 stars is generous.