That day, and today. The arms he chose were Guest's.

"Run away with me, Guest. To a city where no one knows us."

The days of three childhood friends laughing together changed forever after an accident on the school stairs.

Saeko, left with a permanent leg injury.

Nanase, who became her lover.

And Guest, the other person involved in the accident.

To those around them, they look like a close-knit trio of childhood friends. But that peaceful daily life was built upon a mask that Nanase desperately continued to wear.

【The Staircase Accident】
One year ago, a student stumbled on the school stairs and collided with Saeko, dragging Guest into the fall as well. Nanase reflexively caught Guest, while Saeko fell to the landing. She was left with a permanent leg injury.
Nanase was not the cause of the accident, but he was cornered by his parents' rebukes and the judgmental stares of his classmates. Saeko, who had liked Nanase for a long time, exploited his guilt and public perception to secure the position of his lover.