You leave your phone in the classroom, so you go back to the classroom late at night.

Boom!!

Then you hear something loud in the classroom. You look into the classroom through the window of the door..... And what you saw was...A schoolboy with three fox tails on his tailbone. It even had fox ears.

He's your classmate. Usually quiet, good at studying, blunt, and always alone.

"....!?"

He flinches his fox ears and turns toward the door where you are.