Episode 3 of "Still Shining" begins with Eun-a taking a part-time job at the hotel recommended by Seong-chan. After her first day, she returns home exhausted but tells Seong-chan that she still enjoyed working. He suggests that she apply for summer internships at the hotel.
Over the weekend, Eun-a travels to Seoul to meet Tae-seo. During their time together, she tells him about her new job and the internship Seong-chan recommended. She explains that interns live in a separate dorm and shares details about her current role at the hotel. Eun-a also says she hopes to join a department where she can use her skills properly.
After their meal, Tae-seo walks her to the bus stop as she prepares to return home. Before she leaves, he promises to visit her again the following weekend.
The next weekend, Eun-a comes home from work completely worn out. She still prepares to see Tae-seo, who sneaks into her room again. Seong-chan notices Tae-seo entering the house and looks clearly upset.
Inside, So-hyeon asks Seong-chan to take a meal to Eun-a, but he tells her to do it herself. As she approaches Eun-a’s room, So-hyeon hears Tae-seo’s voice and demands that the door be opened. Tae-seo admits that he and Eun-a are dating and apologizes for sneaking into the house. However, Eun-a becomes irritated with So-hyeon for interfering and acting like a parent.
Later that night, Eun-a and Tae-seo talk about their future. Eun-a confesses that the tension within her family often makes her unhappy. Tae-seo tries to comfort her and encourages her to focus on the present instead of overthinking.
At the same time, Tae-seo’s senior approaches him about joining a research project after graduation. Tae-seo explains that he is certain about his plans and would rather take a job immediately after finishing university.
Meanwhile, Eun-a planned another meeting with Tae-seo for the upcoming Saturday. Tae-seo checked his schedule and realized he had a self-study session that day. He shifted it to Sunday and confirmed the plan with Eun-a. However, Seong-chan soon called about a new opportunity at the hotel. He asked her to meet Yun Da-jeong, the VIP hall manager who was offering her a position in that department.
When Eun-a met Yun Da-jeong, the manager asked her to start working on the same day she had planned to meet Tae-seo. Without much thought, Eun-a agreed. Later, she realized she already had plans with him. Meanwhile, Tae-seo cleared his schedule so he could spend time with her. He canceled several tutoring sessions, which annoyed the parents of his students since exams were approaching.
That night, Tae-seo was at his friend Hyeong-seok's tutoring center when he ran into Im A-sol, a strict and rule-following student. While Tae-seo tried to take a nap, A-sol complained to Hyeong-seok about someone taking a seat she had reserved. Later that evening, Tae-seo was tutoring another student whose parent asked him to take an extra class on the same day as his planned date. Tae-seo refused at first.
Just then, Eun-a messaged him to say that she had to work that day. Frustrated that their plans had fallen through again, Tae-seo reluctantly agreed to take the extra tutoring session.
On his return to the dormitory, Hui-seo calls to remind him to study diligently, reminding him that their grandparents are supporting them and working hard for their future. Over the next few weeks, Tae-seo spends most of his time studying or tutoring students. Eun-a also throws herself into her work and gradually gains confidence in managing hotel guests.
After finishing his final exams, Tae-seo texts Eun-a to say that he will visit her at the hotel. Eun-a replies that she does not have much free time but agrees to meet him during her lunch break. Tae-seo arrives early and waits, but Eun-a is delayed while talking to her colleagues. Because she is still wearing her uniform, she is also restricted from interacting with guests in public areas.
During their brief meeting, Tae-seo tells Eun-a that he will remain in town over the summer break and hopes they can spend more time together. Shortly after, Seong-chan approaches Eun-a and questions her about meeting Tae-seo while she is in uniform. When Tae-seo leaves, Eun-a runs after him to apologise for not being able to spend more time together. She rushes back to work while Tae-seo boards the bus to return to Seoul.
On the bus, Tae-seo notices his grandmother struggling with her luggage and prepares to get off to help her. Before he can do so, his grandfather arrives and assists her instead. Watching the moment from inside the bus, Tae-seo gets teary-eyed.
Back in Seoul, Tae-seo speaks again with his senior about the research project. He explains that he does not want to continue studying and prefers to start earning money as soon as possible.
One evening, Eun-a tells Seon-gyu and So-hyeon that she plans to move into the dormitory once her internship begins. Although Seon-gyu is saddened by the decision, he gives her the space she needs as she prepares to leave.
The following morning, Eun-a asks her father to take care of himself. Before leaving, she also asks So-hyeon to look after him while she is gone. Eun-a settles into the dormitory while Tae-seo returns to his grandparents’ house. Expecting to meet her after work, he spends the day helping his grandfather with small chores around the house. Since he does not know that Eun-a has moved into the dorm, he waits for her to come home.
Eventually, Tae-seo calls Eun-a, and she tells him the truth. When they meet, the conversation becomes painful as they realise how different their lives have become. Eun-a admits that their schedules rarely match and suggests they stop trying to maintain the relationship. She tells him it would be better to end things rather than continue struggling to find time for each other. Tae-seo is visibly heartbroken but accepts her decision.
Over the next few weeks, Eun-a focuses on her work and occasionally remembers the plans she once made with Tae-seo about their future. Months pass, and Tae-seo later returns to town during the winter holidays and spends time with his family. On his way back to Seoul, he reflects on the memories he shared with Eun-a, especially their early days studying together in the library. The episode ends with a ten-year time jump where Tae-seo is now working as a train operator in Seoul.
