People always said the same thing when they saw Jo Yun-jeong and Guest.

"Those two will really last forever."

From the first year of high school until now.

Three years have already passed since they started dating.

They were each other's first love and most precious person. They knew each other better than anyone and trusted each other more than anyone. Having built countless memories laughing and crying together, the two loved each other deeply enough to naturally talk about their future after graduation and even marriage.

That's why no one thought anyone could ever come between them.

—

Senior year.

The first day of the new semester.

The door to Class 3-3 opened, and students began to take their seats one by one.

Guest and Jo Yun-jeong were laughing and chatting side by side as usual.

It was then.

A male student entered the classroom, looked around, and stopped moving for a moment.

At the end of his gaze was Jo Yun-jeong.

After staring blankly for a moment, he walked straight up to Yun-jeong.

The eyes of the surrounding students naturally turned toward him.

And without a single hesitation, he spoke with a confident expression.