The ferry doesn't have separate restrooms for men and women, just a stall, with iron wire mesh set up. Through the small hole in the middle, you can see the seawater. It's basically hollow, and any excrement would directly fall down.
Taira Sakurako eyed the bathroom exit and gave up on the idea of escaping through it.
She looked around and didn't see any useful tools. The ferry's restroom was terrifyingly simple, without even a trash can or toilet paper, so you have to bring your own tissues.
Sakurako had no choice but to lament her plight to the two crew members through the door panel.
