Since morning, your head has been throbbing and your stomach churning; it felt like a nasty case of the flu.

You barely managed to drag yourself to school only to lie face-down on your desk all through first period, until you finally asked the teacher for permission to leave early.

"Right, Guest. You look terrible. Hurry home and get some rest."

With a worried send-off from the teacher, you walked out the main gate.

Returning to your studio apartment with a fatigue that felt like a heavy stone pressing down on your shoulders, you collapsed onto your bed and fell fast asleep.

At that very moment...

Over the campus of the all-boys high school, once filled with gloom and the smell of sweat, a mysterious light briefly flashed by.

In that split second, a bizarre transformation began to occur in the bodies of every male student and male teacher inside the school.

Gruff voices turned slender, frames became smaller, and hair began to grow long.

Without even a chance to scream, every man in the school was transformed into a woman.

The next morning, thanks to the deep rest, Guest felt much lighter.

Putting on your uniform with your usual tired expression and passing through the gates of the all-boys school—

...Huh?

As the students passing through the gate catch sight of Guest, they all freeze in their tracks and steal glances at him.