Kids hate her just because she’s ugly. And for the same reason, her crush cruelly rejects her confession. Thinking of ending her life, Ju Kyung stands at the edge of a rooftop. That’s when Su Ho jumps in to save her. Days later, Ju Kyung comes across some makeup techniques, and she can’t believe her own eyes. On her first day as a transfer student, kids are captivated by Ju Kyung’s looks.
As soon as Su Ho sees Ju Kyung at the comic book store, he recognizes that it’s the same girl he saw on the rooftop. He’s kind of disappointed that she doesn’t seem to remember him. Ju Kyung is anxious to see how Su Ho will react at school the next day, but strangely he doesn’t seem to recognize her at all.
It seems Su Ho knows that the no makeup Ju Kyung at the comic store is the same person as the made up Ju Kyung at school. Ju Kyung feels anxious that he might tell everyone about how ugly she actually is. She promises him that she’ll do anything he asks, but it starts to wear her out.
Ju Kyung prepares to go on a blind date. She asks her mother for help at her hair salon, but then Seo Jun steps into the salon when Ju Kyung’s not wearing makeup on her face. She tries to avoid meeting him. Meanwhile, Su Ho participates in a maths competition, but he keeps feeling bothered by the fact that Ju Kyung is meeting with a man on a blind date.
Su Ho goes all the way to meet Ju Kyung late at night with a lame excuse. Ju Kyung starts to wonder if Su Ho has feelings for her. She asks him out. Meanwhile, a first-year student is bullied by her classmates for her ugly looks. This reminds Ju Kyung of her past school life and she decides to offer help.
Su Ho’s father visits Saebom High School to meet Su Ho’s teacher. Everyone at school gets surprised by the fact that Su Ho’s father is actor Lee Joo Hun. Meanwhile, Ju Kyung runs into the bullies who used to harass her before transferring to Saebom High School. Su Ho happens to see them and decides to help Ju Kyung.
Ju Kyung’s heart doesn’t seem to calm down whenever she sees Su Ho. Unfortunately, she finds out that there is already someone whom Su Ho likes. Devastated and disappointed, Ju Kyung begins to naturally avoid him. Meanwhile, Hyung Jin, the ace baseball player from Seonil High, confesses his feelings to Ju Kyung. Knowing this, Seo Jun and Su Ho also feel the surge of affectionate feelings for Ju Kyung.
The students of Saebom High School go on a school trip. Su Ho makes up his mind to tell Ju Kyung that he has feelings for her and even buys jewellery for her. However, Ju Kyung gets heartbroken, thinking that Su Ho likes Soo Jin. Meanwhile, Hee Kyung gets transferred to a different department at work without prior notice.
Not long after reassuring each other’s feelings, Ju Kyung and Su Ho initiate a movie-like plan to keep their relationship secret at school. However, doing so makes it difficult for them to enjoy a typical ordinary date. Su Ho even puts up with embarrassing moments for Ju Kyung. Meanwhile, Seo Jun is having trouble getting over Ju Kyung when he bumps into her at the least expected place.
Ju Kyung still doesn’t want to let her friends know that her boyfriend is Su Ho. Soo Jin tells Ju Kyung that she plans to tell Su Ho that she has feelings for him. Ju Kyung gets torn between love and friendship. Meanwhile, Su Ho and Seo Jun happen to meet at Ju Kyung’s house and start to make dumplings with Ju Kyung’s family.
After stumbling upon the truth behind Se Yeon’s death, Su Ho gets into an accident as he runs out of his dad’s office, and Seo Jun also gets involved while trying to save Su Ho. Hospitalized in the same room, Soo Ho and Seo Jun get to know each other a little better. Meanwhile, Ju Kyung and Su Ho come to an agreement that they are both responsible for the fight earlier. However, Su Ho can’t seem to shake off a bitter feeling.
At school, Su Ho comes back to his class, and Ju Kyung runs into Hye Min who just transferred. Hye Min asks Ju Kyung if they know each other, but Ju Kyung denies and keeps avoiding her at school. Meanwhile, Soo Jin and Se Mi make a deal, and Se Mi shares with Soo Jin the photos of Ju Kyung without makeup on her face.
A video of Ju Kyung sends the whole school in turmoil. When Ju Kyung finds out that her past from the old school has been exposed, she runs away. However, it doesn’t bother Su Ho a bit what others are saying. The only thing that worries him is whether Ju Kyung is okay or not. Meanwhile, Seo Jun does whatever he can to get to the bottom of this happening and is shocked when he finds the person responsible for the video.
Ju Kyung comes back to school and makes up with Soo Ah. Everyone at school finally finds out that Soo Jin was the one who uploaded the photos and videos of Ju Kyung being bullied. Meanwhile, Soo Ho and Ju Kyung go on a trip to the sea, but Su Ho forgets to bring his cell phone. Seo Jun desperately tries to reach Su Ho.
Ju Kyung and Su Ho have no other option but to accept the breakup. After, Ju Kyung stumbles upon the fact that Su Ho is the very boy she met at the Prince Comics when she was young and struggles even more. Meanwhile, Seo Jun finds it difficult to hide feelings towards Ju Kyung and decides to act upon it. Confused by Seo Jun’s unexpected confession, Ju Kyung heads out to Namsan where she bumps into someone.
Ju Kyung and Su Ho finally confirm that their feelings for one another haven't changed after all these years. After shedding tears from their reunion, they start their happy relationship, which is more grown-up from their high school days. Meanwhile, Seo Jun, who has now moved on from his unrequited love, gets ready to debut while Hee Kyung asks Su Ho to include "Missing Love" on Seo Joon's debut album.
