What happens when the infamous gang leader known for his cool demeanor turns out to be a dork who loves idol groups, animals, emoticons, photography, and vibrant colors?
Chaos.
For the simple and average Jung Jieun, getting her hands on a seemingly ordinary notebook wasn't supposed to give her life a complete turnover. However, when the notebook turned about to be the diary of Infinite's popular leader, Kim Myungsoo, her ordinary life immediately turned into one, big, rollercoaster ride.
Gangs, friends, secrets, confessions, heartbreaks, and a diary.
How will Jieun escape this brand-new exhilarating and wild adventure when it has become difficult to find the exit?