One summer day. - Aika didn't realize that she was drinking more water than usual. - (...!!) The sudden urge to urinate comes unexpectedly. - (Ah... the limit...) After all, we're on a train with no escape. - There were office workers and students around who seemed to have some free time. - Passionate gazes of curiosity showered upon me mercilessly. - Before long, men's hands begin to reach out to Aika's body, which has no choice but to stand still in fear and shame... - "Hey, stop it!...Are you okay?" Aika thought that voice was her savior. - That's what I believed. - However, this voice of salvation was the beginning of an eternal hell...