Jae-yeol wants to tell Hee-jin how he feels about her, but Hee-jin ends up misunderstanding his true intention. Hyun-o asks out Hee-jin, and it makes her even more confused. Meanwhile, Jae-yeol finds out that he lost the hard drive that has all the work of his commercial footage. Hee-jin ends up helping Jae-yeol find the hard drive, and Jae-yeol finds another chance to confess his feelings.

Hee-jin comes back to Korea after a year in the US. As she returns to school, she encounters Jae-yeol, her ex. Meanwhile, she also runs into Hyun-o, her first crush from when she was little. As the three coincidentally keep bumping into each other, a whirlwind of emotions ensues.

While Jae-yeol's suspicions grow, Hee-jin applies for a scholarship program in the US. Things become more uncomfortable with the realization that the two must stay apart if she is accepted. On top of that, Ji-won also decides to go to the US to stay with his parents and sister.

Just as Hee-jin and Jae-yeol find happiness, disaster strikes Hee-jin's family finances and her crucial art project is jeopardized. Reeling from setbacks and leaning on Ji-won for support, she unknowingly fuels Jae-yeol's suspicions. Their fairytale beginning crashes hard against grim reality.

Jae-yeol and Ji-won's war of nerves escalates after the incident of the Confession Tree. While Jae-yeol is tormented between Hee-jin and Yeo-reum, he finds out about the truth behind his breakup with Yeo-reum. Hee-jin and Ji-won keep running into Jae-yeol and Yeo-reum, and they end up sharing a meal together at the same table.

Multiple misunderstandings build up between Hee-jin, Jae-yeol, and Ji-won, causing Hee-jin to believe that Jae-yeol still has feelings for his ex, Yeo-reum. Meanwhile, the campus bustles as the school festival approaches with the Confession Tree event, planned to be hosted by Yeo-reum.

Hee-jin and her friends find out that Jae-yeol and Yeo-reum were a couple a few years ago. Hee-jin doesn't show it to others, but she's bothered by it. Jae-yeol tells Hee-jin that there's nothing between him and Yeo-reum, and this makes Hee-jin relieved. Watching them, Ji-won gets confused about his feelings toward Hee-jin. Meanwhile, Yeo-reum comes to school to see Jae-yeol again.

Hee-jin tells Jae-yeol what happened that night, thinking he would be embarrassed about it. However, Jae-yeol doesn't get startled by it, and he confesses his feelings again. Hee-jin is still in doubt, but unexpected events make her think about him again. Meanwhile, Yeo-reum, who is a popular sports announcer, comes to school, and it seems like she and Jae-yeol have a history.

After checking the conversation between A-rang and Ji-young, Jae-yeol runs to Hee-jin, worrying that she would be fooled by bad guys again. However, Hee-jin thinks what Jae-yeol does is cross the line and doesn't listen to him. Out of concern, Jae-yeol asks Ji-won for help. Meanwhile, Hee-jin finally gets to see the real side of A-rang.

A-rang agrees to do the alumni interview as Hee-jin asked him to. Seeing Hee-jin getting closer with A-rang, without knowing, Jae-yeol is concerned about Hee-jin and tells Hee-jin that A-rang isn't a nice guy. Meanwhile, A-rang wants to see Hee-jin in private, and he invites her to his studio.

Bunny is determined to pay back her debt of 2,000 dollars. However, she lacks the means to do so and decides to work part-time at an exhibition. There, she meets another handsome guy. Bunny also decides to enter a strength contest to win a brand-new tablet and be freed from her debt and notetaking.

When it comes to dating, Bunny cares about looks. Having high standards for men, however, good-looking guys have no interest in her. Therefore, she ignores her boyfriend, Bong-soo's looks. Meanwhile, Bong-soo makes a big mistake and humiliates Bunny. Bunny was going to take a leave of absence, but she changed her mind immediately after bumping into a good-looking guy.