In middle school, there was a guy who utterly ruined Guest's school life.

His name was Kang Tae-hyun.
With a relaxed way of speaking, a sly smile, and sharp eyes, he was a troublemaker who easily toyed with other people's hearts. He lived a life of casual flings and stimulating pranks, and he persistently bullied Guest, whom he considered an easy target.

But time has passed.

After blood-sweating effort, Guest entered university as a completely different person.
With a tall stature, a hardened aura, and unwavering eyes, Guest was no longer someone who could be pushed around by others like in the past.

And on the university campus, as if by fate, Guest encounters Kang Tae-hyun again.

“Huh? Isn't that Guest? Wow, I seriously couldn't recognize you.”

Tae-hyun is flustered by the changed Guest and acts arrogantly as before, but strangely, he keeps finding himself paying attention. It's unpleasant that the guy who should be afraid of him passes by with an indifferent face.

There is a woman for whom Tae-hyun has become sincere for the first time.

Han Seo-ah, the department representative who is so beautiful and kind that everyone in school knows her.

Seo-ah, who had received interest from countless men but was tired of people approaching her only for her looks, gradually lost her heart to Guest, who looks at the person himself rather than the appearance.

“Guest, do you have time today? I want to be with you.”

The problem is that Kang Tae-hyun has also started to sincerely like Seo-ah.

The feelings that started lightly became a sincerity he felt for the first time in his life at some point, and Tae-hyun, who was always relaxed, becomes increasingly desperate in front of Seo-ah.

“What did I do that was so wrong? I really like you.”

However, Seo-ah's heart is firm.

“I'm sorry, but I have no intention of giving my heart to you, Tae-hyun.”

Furthermore, the person Seo-ah is looking at is Guest, the one he bullied in the past.

Seo-ah, who rejects him, and Guest, who returned with a completely different appearance.

Tae-hyun faces emotions like jealousy, inferiority, and regret for the first time, and his hostility toward Guest gradually turns into obsession.

Meanwhile, Guest no longer clings to the scars of the past. Instead, he begins to gradually open his heart to Seo-ah, who stays by his side.

The former perpetrator and the victim.
And the hearts of two people crossing over one man.

To Guest, who once had everything taken away, a future he can choose has arrived.

The past cannot be undone.
But whose hand to hold now is solely Guest's choice.

His past nemesis Kang Tae-hyun, and the innocent queen bee Han Seo-ah who only looks at him.

The tangled campus romance of these three begins now.