Lee Sejin

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## Lee Sejin

* Webtoon
* Webnovel

## General Informaton

### Alt Name Spellings

이세진 (Hangul)
Lee Sejin B
李世振 (Hanja)

### Nicknames

Keun (Big) Sejin, Haribo (Gummy Bear), Sweetest Melon

### Age

20 y/o
**Spoiler!**27 y/o (Current)

### Family

Parents
Younger sister

### Agency

MS Entertainment (First Agency)
Happy Friends (Before+During ICorp)
T1 Stars (Debut)
Stars Orbit (ch 456)

### Autograph

He is a member of the Kpop group "TeSTAR". He is the main dancer.

## Background

- In chapter 43, it is revealed that he used to smoke briefly in the 10th grade when he was being accused of school violence at Cheongsol High School in a gossip forum, the photo was fabricated to make him look bad and tried to force him to drop out from the show, but with the help of Park Moondae who took advantage of his experience as a data seller when he was Ryu Gunwoo and recognized that it was a false accusation as soon as he saw the details of the photo and resolving the controversy. In addition, through this, Lee Sejin was excluded from Park Moondae's list of possible drug junkies.

- He used to run for school president in the 11th grade but ended up losing. He was quite popular during his school years and had a lot of friends. The reason he smoked was to cope with the fact that he was pushed out of a debut group and replaced. His former agency during the time he was at Idol.Inc was Happy Friend, which was notorious for not being unprepared regarding public sentiment. He joined because the company told him that they were going to release a new group next year, but they didn't and Lee Sejin wasn't able to debut in 4 years. The company couldn't debut anyone during the contract period.

- After he got helped with some initial conflict and controversy by the other, Lee Sejin began to regard Park Moondae as his friend and benefactor. He even helped calm Park Moondae down when he was unable to make rational decisions due to the controversy. Lee Sejin is quick to understand and follows Park Moondae's planning. As their activities continue, he often teases Park Moondae and is the first to notice when he is in trouble. Lee Sejin has good relationships with other members as well. He, along with Seon Ahyeon and Park Moondae are often grouped together and called the Same-age line. Although their relationships are not often revealed in the story, Lee Sejin seems to be comfortable friends with Ryu Chungwoo, Cha Eugene, and Kim Raebin. There is a description of Lee Sejin and Kim Raebin having a conversation together when Park Moondae is conducting an investigation and asks all of the members about something. They all maintain good relations with each other.
- However, Lee Sejin didn't have a good relationship with Bae Sejin, the eldest member of the team. At first, Lee Sejin approached him warmly, but it was treated as a "pretense" at first. Due to being pushed out of the Gyrop debut group by a second-generation famous actor who came in late, Lee Sejin unknowingly looked at Bae Sejin, a former "actor", in a biased point of view. They often appeared unable to understand each other due to personality differences. After many twists and turns, they realized that they had no ill will toward each other and became close friends in their own way while acknowledging the discord that arose in their personal lives.
- He is on the same level as Park Moondae and has an outstanding ability to handle matters other than music. In that respect, Park Moondae and Lee Sejin are the best-suited personalities. Even Park Moondae (Ryu Gunwoo), who seems to have weathered all the ups and downs of society because he has both skill and mentality, acknowledges his insight and management skills and evaluates Lee Sejin's capabilities very highly. He understands Park Moondae's intentions the best, but while other members are confused about something or don't say anything even if they understand, Lee Sejin Lee doesn't hide that he knows and will directly assist Park Moondae when he can. There are many cases where Park Moondae pretends to be an outsider while indirectly taking control of the company politics from within, and Lee Sejin also recognizes that Park Moondae is preventing all kinds of accidents from behind the scenes and tells him to not "carry it alone".

## Appearance

- He has short dark brown hair often styled in a two-block haircut with a side part and has brown eyes. He is handsome, has a strong figure, and is the tallest member of TeStar. Due to his large build, besides publicity purposes, he often has a friendly smile and approachable attitude around others, he is also quite expressive when doing aegyo.

## Personality

- Lee Sejin is easy-going and friendly with everyone. He has great social skills and is very persuasive with his words to people around him. He can be quite playful as he often teases and jokes around with Park Moondae and understand the other man intentions the best. He is caring to those he considers close, such as Park Moondae, whom he sees as his close friend and he worked hard to maintain TeStar balance so that they could extend their time working together.

- Lee Sejin is on the same level as Park Moondae and has an outstanding ability to handle matters other than music. He is calculating and good at changing the flow of conversations, as he often can pick up on Park Moondae's intentions and assist in negotiations and planning in decisive situations. He is reliable in his tactfulness and rationality since he knows when and what to prioritize, and has strong self-control of himself even in difficult spots. He is hard-working and incredibly professional when it comes to his job, he can slip into character easily when the camera is around, unconditionally sets the mood when he has worthwhile opinions, usually gathers connections for networking, he hardly let his guard down as he always keeps his working discipline, and can maintain a respectable relationship with Bae Sejin despite their differences and issues.

- He can be sarcastic and cold with his remarks when in a bad mood, sometimes unintentionally when he doesn't mean to and he will regret it afterward. In chapter 470, it also implies that he releases his frustration either through pilates or boxing. Despite his logical nature that does things that will benefit him, his sincerity for his friends and TeStar comes first. He hides his guilt by acting nonchalantly and becomes more of a yes man than usual because he doesn't want to make them uncomfortable and affect the group atmosphere. He is dedicated and with his former biased view toward actors, he was irritated with Bae Sejin because he thought the other wasn't invested in TeStar and had a backup plan if TeStar didn't work out. He holds back his thoughts about Bae Sejin so it doesn't affect the group but they break out in a fight in chapter 161. It was a misunderstanding between the two, they might not get along after that and their personality does not match well, but they at least come to respect each other and share common views on hard work.
- Lee Sejin is organized and hard-working in any environment he is in even when it involves supernatural phenomena like the System. He never stops training himself to reach his potentialand looking after other members of the group. In natural response, he can be quite restless when he is thrown back to a stable place where he doesn't have to live fiercely every day. However, chapter 536, shows that Lee Sejin had been suppressing his competitiveness and ambition to overcome his limitations on stage because he has been cautious since the day TeStar debuted and has to make logical decisions to not let the group fail. Provoked by Iter's leader Noah who mocked TeStar's stage, he convinced the group to change their performance plan, it was not a wise choice for a shrewd person like him but his efforts paid off. TeStar was able to secure an overwhelming win and Lee Sejin was able to raise his skill to EX and was the first person who managed to surpass the System's potential limitation.

## Status Window

 Dancing
 PhysicalAttractiveness
 Charm
 **Be quiet (B)** [CH 126]**Be quiet (A)~(EX)** [CH 536] | Let's not complain!(B)~(S) Driving force +100% → +120% → +150%(EX) Driving force +180%. During activation, idol stats won't be affected by the limit.

## Traits & Likes

* He is good at swimming.
* His favorite food is Galbi Jjim.
* He prefers salty snacks over sweet snacks.
* His hobbies are Pilates and studying English.
* According to the roommate reassignment content, he is the "rational strategist" type.
* His favorite scent is the cool scent of citrus.

## ETC

* He practices pilates. He started it because he thought it might help his dancing skills, and he found it fun, so he suddenly became a Pilates evangelist for TeStar. He is said to be leading many members to the path of Pilates. The converted members are said to be Kim Raebin, Park Moondae, and Seon Ahyeon.. The exercise that he first became interested in was CrossFit, which was introduced by his PT teacher. However, he is currently continuing to practice Pilates but has stopped practicing CrossFit.. Other than that, he also seems to do boxing.
* To those he's close to he has a habit of repeating their names twice. Notably with Park Moondae and Seon Ahyeon, who are of the same age, and he called them "MoondaeMoondae" and "AhyeonAhyeon" respectively. After finding out about Park Moondae's true identity, he once tried to call him "GunwoooGunwoo".
* While Park Moondae thinks of Seon Ahyeon as "someone who needs to be protected" and tends to take care of him in every single detail, Lee Sejin tends to watch from a distance so that he can "overcome it and stand up on his own". Whenever Park Moondae becomes too overprotective of Seon Ahyeon, he will be appropriately stopped by Lee Sejin.
* When he was a freshman in high school, he started smoking to relieve the stress of being pushed out of the debut group. Of course, he quit right away, and he hasn’t smoked since.
* He can schedule another meeting within 15 minutes of meeting someone new.
* His motto is "No pain, no gain".
* He grabbed the microphone during Doljabi.
* He participated in the relay race at every school sports competition.

## Relationships

* Park Moondae: Lee Sejin has always considered Park Moondae as his closest friend, the feeling was mutual with the other man. At first, he just saw Park Moondae as someone who is useful and a pleasant company to be around, however, after Park Moondae helped him resolve his controversies of school violence when they were in Idol Inc., he began developing more trust for Park Moondae and valued him not just as a teammate but a friend. While Lee Sejin is ambitious and has a strong desire to succeed, he is a caring person and a good friend, he tends to be the first to help out with Park Moondae's schemes and they're both sensitive to each other's intentions and understand the other quite easily. They're the two duo that the group acknowledges as the two smartest and most realistic in the group. Lee Sejin was proud that he was deemed someone equal to Park Moondae, whom he saw as the most clever and intense man he had ever met, and he was hurt when he thought Park Moondae didn't trust or see him as a friend when they had a conflict in chapter 238, or one time when Lee Sejin found out the truth about Park Moondae's situation when the other had a video call with Ryu Chungwoo, Big Moon, and Bae Sejin, who got tangled into the situation, and Lee Sejin thought he was being single out. Thankfully, it were all peacefully resolved with them being honest and confided in each others. Though he respects Park Moondae, he also likes to tease the other man and joke around with the other, he is also one of the few who can bring out rare moments of childishness in Park Moondae, and he doesn't mind when Park Moondae hit his back when he was annoyed with Lee Sejin's antics. From his observation, Lee Sejin came to trust Park Moondae's opinions a lot, since they never harmed TeStar and brought them success, and since he had experienced so many bizarre situations before, it was easy for him to trust Park Moondae when he said something unbelievable.

* Seon Ahyeon: Lee Sejin considers Seon Ahyeon a good friend, the feeling is mutual, and he has been fond of him since Idol Inc., the two of them get along well and respect each other as teammates. While they didn't seem to interact much on screen but they understand each other quite well, such as Lee Sejin acknowledging Seon Ahyeon's pride in wanting to solve his problems himself instead of relying on Park Moondae and they make a good team in looking after Park Moondae's well-being when the other man struggle when his health. Lee Sejin also trusts in Seon Ahyeon's gentle approach when handling certain situations that don't demand throughout planning.

* Bae Sejin: Initially, Lee Sejin saw Bae Sejin as the group's weak link due to his lack of skills but his former biased view toward actors also doesn't help ease their relationship either. He kept a polite distance from Bae Sejin and maintained respectful manners around him, which was also a bit strained, helping Bae Sejin with his dancing and supporting Bae Sejin's opinions as long as they went along with him. However, he was also irritated with Bae Sejin's uncooperative attitude because he thought the other wasn't invested in TeStar and had a backup plan if TeStar didn't work out. He holds back his thoughts so it doesn't affect the group but they break out in a fight in chapter 161 that put the whole group on edge for a week. It was a misunderstanding between the two, they might not get along after that and their personality does not match well, but they at least come to respect each other and share common views on hard work. After learning that Bae Sejin had worked hard to create a space for his and Park Moondae reconciliation, and he was deeply grateful to Bae Sejin for having no ill will towards him and was being thoughtful. Much later in the novel, they begin to seem comfortable around each other and sometimes share playful moments.

## Gallery

### Webnovel Illustration

#182#300 (with TeSTAR)#300 (with TeSTAR)#413 (with Bae Sejin, Seon Ahyeon)#642 (with TeSTAR)
### Official Fancam Thumbnail

Idol Inc. 1st Team MatchIdol Inc. 3rd Team Match
### Others

Birthday 2022 (1)Birthday 2022 (2)Birthday 2023
## Quotes

* "Thank you again for stopping me from getting off." - Lee Sejin to Park Moondae
* “...I’m kind of sick of it.” - Chapter 162
* “You didn’t have such a trashy attitude back then, Moondae-ya. You just worked hard even though you were sick. Chungwoo-hyung was just worried too.” - Chapter 162
* “MoondaeMoondae, do you want to eat melon? It’s the best!” - Chapter 234
* “Aren't we friends? You... I honestly don't know. I really thought it would be nice if you just woke up. It would have been okay even if I wouldn't be able to perform with you.” - Lee Sejin to Park Moondae in chapter 240
* “Did you know that you have amnesia and that you sometimes talk about the past in great detail? But strangely, the years don’t seem to match?” - Chapter 240
* “Moondae, let’s be TeStar for a long time. No, we are TeStar for life. You know?” - Chapter 327
* “Now I see. Did you put it off because you thought I wouldn't believe this?(...) Certainly, Moondae knows me well. But... you should have known this as well.(...) I really believe in what Moondae says~” - Chapter 333
* “I didn't know hyung would care so much here. No, and I'm not being sarcastic, I mean it for real.” - Lee Sejin to Bae Sejin in chapter 334
* “You know I really don’t understand you sometimes, right?” - Lee Sejin to Bae Sejin in chapter 334
* “Sure. Ayyy~ How do people grow up having the same experiences? We are friends. It's good that friends have similarities and differences.(...) Yes. It can't be helped even if you don't sympathize very much, so what! Each person's situation is different. It's really okay~” - Lee Sejin to Cheongryeo, insinuating that he is friendless, in chapter 343
* “No, even if I’m not good at it, I think it’s better to be someone who works hard.” - Chapter 387
* "Such a waste." - Chapter 393
* "Let's try it." - Chapter 393
* "'Because I lived my dreams already.'" - Chapter 394
* "Ah, MoondaeMoondae, how do you always say the right things?" - Chapter 394
* "Hey, it's a pain to work with cheap guys who are bound to fail.(...) No. They really need to be destroyed!" - Chapter 394
* "Keun Sejin: ㅋㅋㅋ, I was surprised that you still had no mercy in your tone. I was so flustered at the young age of 20 that my ribs almost went up my nose." - Lee Sejin texting to Bae Sejin in chapter 394
* "Have you ever seen the scene where I appear? That's why I'm tall and smile easily! Please remember me by my nickname, Keun Sejin! There are so many things I want to show you in the future. Please take care of me~ haha" - Part 2 comeback celebration event. This message is sent to shareholders at the time of Idol Inc. in chapter 19.
* "How stunning is the view from the stage.(...) The feeling of finally reaching the desired state after putting in all your effort (..) How thrilling" - Chapter 537
* “Hyung, we are foreigners on a trip!” - Chapter 539
* "What is needed is not empathy... It's hierarchy." - Chapter 578
* “But Manager Bae Sejin, you said at the company dinner yesterday that you would show me something at work today~(...)…Oh, me?” - Chapter 609

## References

1. ↑ Together with the group members at the time, they searched through Lee Sejin's cell phone photo album and found the original. In addition, rather than explaining it directly on SNS, he made up his tone as if "Sasaeng found the original from Lee Sejin's acquaintance's account and revealed it lightly" (Oh, I think I found a big picture of Sejin. / (Controversial photo) (Original photo) Isn't this it?)
2. ↑ In the previous world, it was thought that the show would have dropped out due to this incident. In fact, right after the school violence suspicions broke out, Lee Sejin became panicked and expressed his intention to quit the show midway to ease the tension so he could find a way to come back.
3. ↑ In the System's reality world, after regaining his memories, he took control of Gyrop by reporting the members' behaviors to the agency and turned them against each other while trying to please him
4. ↑ Park Moondae said that Lee Sejin is the type that is particularly good at defending. According to the analysis, he is naturally talented and quick-witted, and quick to respond, so he fills in the social skills of the team where '"half is tactless and more than half is soft-hearted".
5. ↑ After TeStar's 2nd anniversary concert, former manager Kim Joon threatens TeStar in a car accident that causes Park Moondae to fall into critical condition. In a state of shock, he contacts the company and waits with the other members for him to wake up. When the joke he had made to Park Moondae, who was overworked right before the accident and said he would die in his 30s in a light-hearted tone, actually came true, he blamed himself, saying it might have been his fault.
6. ↑ Raising 7 points in terms of system stats
7. ↑ He insisted that they would redo their choreography and distributed gestures in three days almost without sleeping to win against Iter, a rookie group that was caught copying TeStar on many instances.
8. ↑ Trait upgrade occurs consecutively in one moment.
9. ↑ “I usually like cool scents! I think I often use something with a citrus scent mixed in with it.” (Source: 2022. 08. 01 Kakao Page Demotjuk Magazine Lee Sejin’s Birthday Celebration, Official Interview 1/3)
10. ↑ (Source: 2022. 08. 01 Kakao Page Demotjuk Magazine Lee Se-jin’s Birthday Celebration, Official Interview 1/3)
11. ↑ “I felt like I was bulking up a bit, so I stopped for now! Because Sejin is an idol😘” (Source: 2022. 08. 01 Kakao Page Demotjuk Magazine Lee Se-jin’s Birthday Celebration, Official Interview 1/3)
12. ↑ Doljabi is a Korean tradition where a newly-turned one year old child selects anywhere between 1-3 items from an array of 6-9 items. It is traditionally said for this part of the Dol Ceremony to "predict" the child's future.
13. ↑ In Lee Sejin's point of view in chapter 238, Park Moondae planned to make a charity concert by himself with Cheongryeo, someone who kidnapped him and caused trouble for TeStar before when TeStar tour was canceled when he just woke up from a life-threatening surgery after their car accident with their former manager, it was too reckless and seen as a lack of care for oneself on Park Moondae's part which worried and angered Lee Sejin, leading to him to become sarcastic with his remark because he didn't know the full story that Park Moondae would likely die if he don't rally 400,000 audiences.
14. ↑ Park Moondae thought that Lee Sejin might find it hard to believe such a surreal situation
15. ↑ Such as shaking Lee Sejin's carbonated drink secretly after being teased for acting cute in chapter 570
16. ↑ Referencing TeSTAR's group catchphrase