During the zombie outbreak in the city, she and her boyfriend arrive looking to see some zombies in action. Unfortunately for her, her boyfriend falls prey to the undead. As she escapes, a man with a golden eye appears before her with a floppy disc to give to the agents. When AMS agents Stick Breitling, Linda Rotta and Rikiya Busujima arrive, Yoko is seconds away from being killed by zombies.
If she is saved, she will give the disc to the agents and describe the person who gave it to her as someone with a golden eye. As they leave, she asks herself how she got into this mess. If she is killed, she will drop the disc in which the agents can retrieve.
Yoko is not seen again until the game's ending, which will differ depending on her survival. If she was saved earlier, she is waiting impatiently in the same warehouse she was found in, cursing that ZED had better come back with the money he owes her for delivering the disc and after all she went through. If she was killed, her back is shown to the camera, apparently feeding on something before slowly turning her head toward the screen.
- Unlike other hostages in the House of the Dead games, Yoko cannot be accidentally killed by the player.
- Yoko carries the tradition of having a character turn into a zombie with the game's bad ending.