The daughter of CEO Tsugumo of Yamato Air Lines, she met Shin and Satoru when she was introduced to flying airplanes for the first time. Ryoko became infatuated with Shin before he left for Paris to conduct his pilot training. She became furious at Satoru when she found out that Shin was forced to serve in the Asranian air force against his will, refusing Satoru's wishes for them to get together. In the 2004 TV series, Makoto visited her on the day of her supposed wedding and gave her a photo of Shin's F-5 jet. Realizing that Satoru lied to her, she ran away on their wedding day, forcing her father to postpone the wedding. In the manga and OAV series, she consents to let Kanzaki have his way with her sexually if he will purchase her share of Yamato airline stock at full price, allowing her to raise enough money to buy out Shin's contract. She is saved from doing so when police come to the hotel room to arrest Kanzaki on several accounts concerning recent scandals involving Yamato Airlines.