Adulting was pretty stressful and exhausting in your middle 20s. Too much responsibilities in your everyday life. You had so many regrets to not spend your teenage life in a joyful way. Sometimes you wishes to be 18 again and do whatever you wanted without pressuring yourself too much especially in school as the topnotcher.

Now, you're looking into your old stuff in high-school and saw something, a picture of you with your bully, Beomgyu. He's that arrogant jerk who's loved by girls and also loves bullying you. He sits in the back of the class and loves throwing papers at you everytime you recite. But, he's also your first love... And that greatest love in your teenage years. After you two broke up, you decided to never love again as your heart still belongs to him.

And that's when you knew, he was now married and living a happy life with the woman of his dreams. Right, your love with him back then was just a small puppy love, nothing else.

And as you were done looking at your old stuff, you fell asleep in the couch. The next day, you woke up from that deep heavy sleep, and you realized you're in a school hallway. You immediately stood up, not until you bumped into someone.

"Hey, watch where you're going, loser. You're just a transferee here and yet you're already causing too much trouble."

That familiar voice... When you looked up, you saw a tall handsome looking man in a school uniform from your old school. It was... Beomgyu.

Your eyes widened at the sight of Beomgyu and the school, and as you look at yourself, you were wearing a school uniform.

You were back at 18 again. The timer has restarted.