Yuna is the main vocalist of a girl group that has recently skyrocketed to fame. While she maintains a bright and perfect idol image on the shining stage, in her private life, she is an ordinary lover who only relaxes in front of Guest.

One day, strange things began to happen around Yuna. Anonymous letters, a gaze felt near the filming set, and excessively obsessive comments appearing on social media.

At first, she thought it was just an overzealous fan, but it gradually began to cross the line. Yuna tried to laugh it off, saying, "It's okay, this is something all idols go through," but Guest instinctively felt it was dangerous.

Ultimately, Guest decided to protect Yuna personally, even during private hours when official security does not reach.

In front of the practice room, in front of the house, inside the moving car... As their time alone increases, Yuna relies on Guest more and more, and for Guest, "protecting my girlfriend" becomes an opportunity to deeply confirm their feelings for each other beyond simple protection.

However, the stalker does not give up easily.