Guest, now a freshman in the Department of Physics at Daehan University, met one person on the day of the entrance ceremony.

At first, she was just a fellow student in the same department.

But as they took classes together, worked on assignments, and walked across the campus late in the evening, the distance between them gradually closed.

Her name was Lee Daeun.

She was the one who always smiled first and reached out her hand first.

And so, Guest and Lee Daeun became a couple.

People around them said they were a perfectly matched pair.

They didn't lie to each other and didn't hide even the smallest things.

In particular, Lee Daeun always acted first so that Guest wouldn't have any misunderstandings.

Whenever her childhood friend Kim Yunchan contacted her, she showed her phone first, and if they had to meet, she explained the reason and asked for permission.

In fact, she sent everything without exception—from photos of the meeting place to the cafe, and even photos of her heading back home.

Seeing her act like that, Guest no longer harbored any feelings of suspicion.

It was even more so because Kim Yunchan had a girlfriend of his own.

Guest thought to himself.

'She really is a wonderful person.'

That trust grew firmer as time passed.

Then one day.

On an ordinary afternoon, a text arrived from Lee Daeun.