"How far would you go for the sake of revenge?" That is the question that Yuri was faced with when her mother was brutally murdered, and she was held up for charges of her own mother's murder. Nearly a decade later, she is now an accomplished assassin - a member of the underground organisation, Hati, that takes out the people who couldn't be touched by the law, and protects the order of the world. When hints and rumours of a mysterious organisation by the name of Raven's Gate started making themselves known, suspicion and hysteria soon grips the entire organisation. But things aren't as easy as they seem, especially when Yuri's past started catching up to her.