One day, a door was found abandoned in the school hallway. "Is that the one you used at the school festival? It's in the way," I thought as I looked at the door and touched it, but the teacher told me to put it away. I had no choice but to carry the heavy door to the classroom, and while wondering what to do, I thought, ``If I open the door like this, it will lead to the girl who is changing...!! Oh, you're lying, right?!'' It was a mysterious door that could go anywhere, including where the girl was changing, the bathroom, and a private room in the toilet! !