Seong Jae has always loved Sol. He was the one who rescued her when she jumped into the water after she lost her legs. In 2023 before his death, he recognized her as his first love when he saw her again in the road side and had even followed her home.
Sol wakes up in the hospital and asks a passing nurse what the year is. When she hears it’s 2023, she’s devastated. She sees Sun Jae’s father mourning him in the hospital and as she leaves, In hyuk, Sun Jae’s friend and band member sees her. A few moments later, Sol is questioned by the police. They show her a small photo which coincidentally is the picture she and Sun Jae took at the photo booth. They question her as the last person who spoke with him before his death. Seeing the picture makes Sol believe she has changed the future so she goes back to the pond and tries to go back in time but nothing happens.
When Sol returns home, In hyuk surprisingly calls her. He chokes back tears as he tells her that Sun Jae felt bad towards her. When she asks why, the connection cuts.
Sol then discovers that the watch only activates by twelve. At twelve sharp, she goes back in time only to find herself in the midst of an exorcism ritual performed by her mom and grandma because her past self had claimed she was being posessed. Sol insists she’s fine and leaves them to find Sun Jae. She sees him strolling on the streets and immediately meets him but he seems upset and doesn’t talk to her. Sol remembers it’s because her past self didn’t know him and treated him like a pervert when he approached her.
Sol decides to remedy this situation and the next morning, starts chasing him around with gifts. She claims she was possessed. However, Sun Jae tells her that ghosts don’t date, leading Sol to remember her past self had accepted to be Tae Sung’s girlfriend. Sun Jae leaves disappointed and while trying to catch up with him, she trips but Tae Sung comes to her rescue. Sun Jae sees them together and isn’t happy about it. In hyuk blocks his eyes with his hand telling him not to see them.
Sol cringes at the love sick messages she sent to Tae Sung. He talks with Sol and is quick to realize she isn’t the love stricken Sol he knows as the sparkle in her eyes is lost but he doesn’t seem too bothered about it when Sol asks if he likes the love stricken her but he doesn’t give an answer.
Mr Ryu, Sun Jae’s father returns the pot Sol had given him. He then discovers that his troublesome neighbor is her mother. Sol meets with In hyuk and advises him not to bring Sun Jae into his world of music and that if there’s anything he has to tell her in the future, he shouldn’t hesitate. In hyuk is confused about what she’s saying but tells her she should stay away from Sun Jae.
Sun Jae’s rival gets on his nerves, mocking him for being unable to swim. He goes as far as bringing up his late mother, saying she would be disappointed because he didn’t fulfill his promise of joining the national swimming team. They almost get into a fight when Sol appears from nowhere headbutting his rival on the head as she yells at him for talking about his mother. The situation nearly escalates until the teacher who had punished Sol for smoking sees her and she immediately escapes but unfortunately runs into Tae Sung’s ex who tries bullying her. However, they end up in a hair pulling fight. However, they are separated by a familiar looking man. Sol immediately recognizes him as Mr Kim, Sun Jae’s manager from the future. She runs after him only to find him already scouting Sun Jae and In hyuk. Before she could stop them, In Hyuk had already led Sun Jae into the bus.
She goes to Sun Jae’s house and tries to get Mr Ryu to let her in, hoping she can get rid of Mr Kim’s card. She gets her opportunity when Mr Ryu leaves the gate and his front door open in a bid to release himself. Somehow, she ends up in Sun Jae’s room. She finds Mr Kim’s card in his chest pocket and tears it to shreds. Mr Ryu nearly catches her in Sun jae’s room but she says something that happens in the future causing time to stand still so she can hide from him.
Sun Jae arrives home stunned to see Sol in his room sleeping on the ground. At first he thinks he’s seeing things but he soon confirms she’s real. He’s fascinated by her, even measuring their hand size difference but then, a mosquito starts causing a nuisance and while trying to catch it, he finds himself right in front of Sol who wakes at that moment. Sol apologizes for the intrusion, saying she got hit on the head by the books she got for him which caused her to pass out. She feels she has done so many stupid things in front of him and begs him to forget the past and to get along with her like he did before.This triggers Sun Jae as he feels sensitive because of their kiss only to feel foolish when he discovers she doesn’t even remember what happened.
Meanwhile, Tae Seong is concerned because Sol hasn’t called him recently when she’s always the first to reach out. His friend teases him about this, saying he shouldn’t forget that he only dated Sol to get rid of his ex. In hyuk overhears their conversation.
Meanwhile, Sun Jae stops talking to Sol, hiding the picture of them at the photo booth. However, the mosquito shows up again and while trying to catch it, Sol ends up right in front of Sun Jae nearly falling on him if he hadn’t caught her two arms. Frustrated by his overwhelming feelings, Sun Jae covers her in a blanket and carries her outside on his shoulders.
He is mad at her for trying to get along with him as he stresses that boys and girls can not be friends. He’s uncomfortable with the way she treats him and tells her to leave him alone. Seeing her sock covered feet, he gives her his slippers and tells her to go. That night, both are very upset and Sol ends up crying on the bed.
Meanwhile, Geum saves Hyun ju from an embarrassing constipation problem where she publicly shits on herself in front of a group of men.
It’s Tae Sung’s birthday but he feels alone until Sol arrives at the restaurant to accompany him. She wants to break up with Tae Sung but unknown to her, her past self had planned a rather embarrassing yet cute birthday surprise for him, singing songs about how she likes him, even gifting him a teddy bear causing Sol to feel extremely awkward. She later takes Tae Seong to a diner to eat seaweed soup, a staple food for celebrating birthdays in Korea. She then advises Tae Seong that when the innocent one takes over her body, he should treat her well. They shouldn’t engage in sex because they are still so young. However, their conversation is interrupted when Tae Seong shows her a picture of Sun Jae and In hyuk at a music audition.
Sol races over there but only meets In hyuk. She gets angry at him for bringing Sun Jae to the audition but In hyuk is confused on why she continues to poke her nose on Sun Jae’s business especially when she’s dating someone else. He tells her his father came for him but while they are talking, Sol trips over the stairs.
Sun jae is working at his father’s restaurant when In hyuk informs him that Sol came over to see him but ended up tripping on the stairs. Sun Jae doesn’t want to talk about her but he changes his mind out of concern and goes in search of her only to see her asleep in a bus.
When Sol wakes up, she discovers the bus has reached its final stop. It drops her at a secluded street and while Sol is waiting for the next bus, a suspicious looking taxi man tries to pick her up but the appearance of a drunken old man makes him drive by. However, the drunk old man suddenly starts harassing Sol and she tries to escape from him. Thankfully, Sun Jae comes by and starts running towards her but when Sol notices him, an old memory of Sun Jae running over to her just like now resurfaces. While bantering with the old man, Sol falls into the river below her and Sun Jae dives in after her, spiking a memory from before. She remembered Sun Jae was the one who saved her from the accident and when he pulled her out of the river, she started crying remembering when she shouted at him in the hospital because he saved her. Sol can’t believe she forgot him and suddenly hugs him feeling remorse flow through her.
