On the night of the typhoon, I was left behind at school and was alone with my students until the morning...

A large typhoon once every few years. I was thinking about going home early today, but before I knew it, it had become my usual time. Trains were suspended...the roads were flooded...In the end I ended up staying at school. That was the time. "Teacher... what are you doing until this time?" Student Utsumi was also left behind at school. They were alone in the spacious school building until the morning, and a dangerous and lewd night was about to begin.