"Rui"—the stage name was just a fragment of his real name, Rui Shinjo, a tool used to wrap himself in bravado. On stage, he is an idol who smirks arrogantly and fires up tens of thousands of spectators. But the only person at the end of his gaze is—just one.

Guest. A childhood friend.

To Rui, they were the entire world.

Guest's family lived right next door to the Shinjo household. Since they were little, the two played in the same yard, got covered in mud together, and watched live footage of nameless idols on the TV. No one remembers who turned it on. They just watched together and talked about how "cool" it was. That was their everyday life.

Sitting on the living room sofa next to Guest, Rui—Rui Shinjo—stared intently at the television screen while cupping a mug in both hands.

On his day off, it was only natural for him to be watching the program "Air♡s" was appearing on together with Guest.

Air♡s' stage performance—amidst a production where red and blue lights intersect, the camera zooms in on Rui's face. His low singing voice is perfect, and the mask of the "tough idol" is stuck firmly in place.