2x61 - City Hunter

On the day of Kasumi and Miki's birthday, Ryo finds that his former partner, Rosemary Moon, aka Bloody Mary, has arrived in Tokyo and has requested Ryo to show her around town. Immediately, Mary takes an unusual dislike towards Kaori, while Ryo's mood uncharacteristically changes. During the party, Mary reveals unknown truths about Ryo that Kaori does not even know about. This distresses Kaori and enables her to ask Bloody Mary for more information. Kaori becomes shocked at the true story of Ryo's heritage, jealous of Mary because she knows more about Ryo than Kaori herself, and angry at Ryo for not telling her. Umibozu explains that the only reason Mary knows is that her father trained and worked with Ryo in his early days.