Study Group Character Guide: Yoon Ga-min's Full Cast

TL;DR: Study Group character guide, verified against AniList's own character database rather than a fan wiki: protagonist Yoon Ga-min, the study-group allies who back him, tutor-turned-classmate Han-gyeon Lee, and rival Han-wool Phi's ties to the White Lead Gang.

Two other pages on this site already cover Study Group from different angles. The Study Group manhwa review covers whether the 8.0-rated series earns the read. The Study Group reading guide covers where to start and how the TVING drama maps onto the manhwa. Neither page names more than Ga-min himself. This guide does that specific job: every character AniList's structured database confirms by name, checked directly against the series' own entry rather than pulled from a wiki page nobody's kept current.

Key Takeaways

• Yoon Ga-min, AniList's "Ga-Min Yun," founded the study group himself after being turned away from every other one at Yusung Vocational High School.
• Han-gyeon Lee is Ga-min's former private tutor, now enrolled at the same school while working toward her own teaching certification.
• Ji-woo Lee and Hyeon-u Lee are twins. Ji-woo, the elder, is a study-group member majoring in chemical engineering and trained in Judo.
• Han-wool Phi is the son of a director in the White Lead Gang, the closest thing this cast has to a documented antagonist lineage.
• AniList's relations data ties Study Group directly to five other YLAB webtoons, plus a documented character-level crossover with fellow YLAB title Daejangjeon.
• Every name here is checked against AniList's character database for media ID 110472 and WEBTOON's own official synopsis, not a fan wiki.

Overview

Study Group has been serializing since January 4, 2019, first on Naver Webtoon and now in English on WEBTOON, written by Shin Hyung-wook and drawn by Ryu Seung-yeon for publisher YLAB. AniList lists it as still releasing with no chapter total attached. That tracks. It's an active webtoon, not a series someone's tallied up after the fact.

The premise is small on paper. Yoon Ga-min wants into a four-year university, and he can't find a study group willing to have him at Yusung Vocational High School, a school WEBTOON's own synopsis describes as a place where it's "every man for himself." So he starts one. What complicates that plan is the one thing Ga-min is actually gifted at: fighting.

This guide profiles the people who orbit that plan, checked against AniList's structured character database rather than assembled from memory or a wiki page someone stopped updating years ago. The tally is thin: six named characters carry a listed role in the entire entry, which says something about how tightly YLAB has kept this cast even after several years of ongoing serialization. A shorter, accurate Study Group cast list beats a padded one, so that's what this guide sticks to.

If this grounded, technique-first ensemble is what you came for, this is the wider list built on the same design philosophy. .

Manhwa Like Study Group →

Study Group Character Guide: Yoon Ga-min, the Honor Student Who Fights

AniList's card lists him as "Ga-Min Yun," the same person this site calls Yoon Ga-min elsewhere, just in the Western given-name-first order the database defaults to. The card carries two details worth knowing beyond the name order. His listed hobby is simply "martial arts," and his classmates call him "Crazy Glasses," a nickname that survives the jump from Korean into the English localization intact. He's 178 cm, per the same profile.

Ga-min's stated goal, straight from AniList's own summary, is blunt: get into a four-year university, become a college student. WEBTOON's official synopsis fills in why that's hard. Yusung Vocational High School is nicknamed "the school for future criminals," and Ga-min gets turned down by "countless study groups" before he stops asking and builds his own. AniList's bio attaches a line to him that reads less like a summary and more like an actual character motto: "To hell with circumstances, I create opportunities." That's not a paraphrase. It's pulled directly from the character's own listed description, and it's a tighter summary of Ga-min's whole arc than most recap coverage manages in a full paragraph.

The site's review and reading guide already cover the fighting itself in detail: grounded, technique-first choreography described there as Jeet Kune Do, the real-world martial art most associated with Bruce Lee. What neither of those pages does is put a name to who Ga-min is actually protecting when he fights. That's the rest of this guide.

Ga-min's official character art from AniList's database. The loosened tie and raised fists say more about him than the neat uniform does.

The Study Group's Core: Han-gyeon Lee, Ji-woo Lee, and Hyeon-u Lee

The group Ga-min builds isn't a faceless prop sitting in the background. AniList's character list confirms three more names tied directly to it, and WEBTOON's own synopsis names the most important one first.

Han-gyeon Lee is listed alongside Ga-min as one of only two characters tagged "MAIN" in the entire cast, and she isn't a classmate. She's Ga-min's former private tutor. WEBTOON's synopsis describes her arriving at Yusung Vocational High "in hopes of earning her teacher certification," which puts her in an unusual position relative to everyone else in the story: she taught Ga-min before the series starts, and now she's back in the same building, working toward a credential instead of a diploma. That's a specific, sourced relationship, not a guess, and it's a sharper setup than the "childhood friend" or "mysterious transfer student" defaults this genre usually reaches for.

Ji-woo Lee and Hyeon-u Lee are twins, and AniList is explicit about the birth order: Ji-woo is the elder. Her own character card lists two more specifics beyond that. She's majoring in chemical engineering, and she's trained in Judo. She's also directly tagged as a member of the Yusong High study group, which makes her the one piece of documented backup Ga-min has beyond Han-gyeon herself. Hyeon-u's own card doesn't carry the same depth of detail. What's on record is the sibling relationship and his place among the cast's supporting characters; what he actually does across the story's chapters isn't spelled out in the same source. Better to say that plainly than guess at a personality for him.

One more name shows up in AniList's supporting cast without an attached description at all: Young-ha Jeon. He exists in the listed roster, tagged the same way Han-wool Phi and the Lee twins are. What his role actually is hasn't surfaced in a source this guide could independently verify. A short, accurate entry for him beats a longer, made-up one, so that's where this one stops.

Ji-woo Lee's official character art. She's the study group's one confirmed backup fighter beyond Han-gyeon, trained in Judo.

Study Group Character Guide: Han-wool Phi and the White Lead Gang

Every school-fight series needs an opposing pressure, and Study Group's most concretely documented one runs through Han-wool Phi. AniList's card on him is short but specific: he's the son of a director in the White Lead Gang, a man named Yeonbaek Phi. That single confirmed detail does real work. It means the threat facing Ga-min's study group isn't just a tougher kid at school. It's a kid with an actual criminal organization standing behind his family, the same institutional-violence structure that recurs across YLAB's wider catalog.

That catalog is bigger than the "Blue String Universe" branding this site's other Study Group pages mention in passing. AniList's own relations data for Study Group ties it directly to five other YLAB titles: Get Schooled, Hanlim Gym, To Not Die, The World is Money and Power, and further entries not yet carrying an English title. It goes past a shared-universe label, too. AniList records a documented character-level crossover between Study Group and fellow YLAB series Daejangjeon, the kind of connection that only shows up when a publisher is deliberately building one continuity rather than just reusing a house art style across separate books.

Get Schooled is the clearest parallel worth naming directly here. Where Han-wool Phi represents gang authority pressing in on Ga-min's world from outside the school gates, Get Schooled's Na Hwajin is a government inspector using sanctioned force to push back on failing schools from the top down. Same publisher, same underlying question about who gets to use violence and why, pointed in opposite directions.

Readers chasing this exact dynamic, a school setting where the fighting actually drives the plot instead of decorating it, tend to end up cross-referencing the wider best school setting manhwa list to see how many other titles run on the same structure.

Han-wool Phi's official character art. His father directs the White Lead Gang, the closest thing this cast has to a documented antagonist lineage.

For where this cast and its fight choreography rank against the wider genre, see the ranked roundup. .

Best Action Manhwa 2026 →

Step-by-Step

1. Start with Ga-min and Han-gyeon. They're the only two characters AniList tags "MAIN," and their relationship, former tutor now sharing a classroom, sets up most of what follows in the cast.

2. Add the twins as a pair, not two separate introductions. Ji-woo and Hyeon-u share a surname, a birth event, and, for Ji-woo specifically, a documented study-group membership. Learning them together avoids mixing them up later.

3. Note which twin is older. Ji-woo is the elder per AniList's own card. It's a small detail, but it's exactly the kind of thing casual recap coverage gets backwards.

4. Place Han-wool Phi outside the school, not inside it. His threat comes from his father's position in the White Lead Gang, an external pressure rather than a rival classmate picking a fight for its own sake.

5. Treat "Blue String Universe" as a specific list of titles, not a vague label. Get Schooled, Hanlim Gym, To Not Die, and The World is Money and Power are the ones AniList's own relations data confirms are directly tied to Study Group.

6. Move to the reading guide once the names are straight. This site's separate Study Group reading guide covers where to actually start reading; this page exists so the names in chapter one aren't still a blur by chapter twenty.

Tips

Don't assume every named AniList entry gets equal page time. Young-ha Jeon appears in the listed cast without an attached description. That's a signal he's a minor or later-arriving name, not an error in this guide's research.

Watch for name-order swaps. AniList's structured fields render "Ga-Min Yun" and "Han-Gyeon Lee" in Western given-name-first order. This guide uses the family-name-first form the rest of the site already established, Yoon Ga-min and Han-gyeon Lee, for consistency across the cluster.

Han-gyeon's role is a teacher-track student, not an actual teacher yet. She's working toward her certification, per WEBTOON's own synopsis. She isn't a licensed instructor when the story opens, and that distinction shapes how she actually behaves around Ga-min rather than lording authority over him.

Don't fold the White Lead Gang into "just another delinquent crew." Han-wool Phi's confirmed family tie makes it an organized structure with its own leadership, closer to the institutional threats Get Schooled runs on than a loose group of tough kids looking for a fight.

Related Reading

• Study Group Manhwa Review: the full 8.0/10 verdict on whether the grounded fight choreography earns the read.
• Study Group Reading Guide: where to start reading and how the TVING drama maps onto the manhwa.
• Manhwa Like Study Group: eight picks for readers who came for the grounded, technique-first fighting.
• Get Schooled Manhwa Review: the closest YLAB title, institutional force pressing down instead of a gang pressing in.
• Best Action Manhwa 2026: where Study Group's cast and choreography rank against the wider genre.
• Best School Setting Manhwa: more series that use the school itself as the actual engine of the plot.

Frequently Asked Questions

Who is the protagonist of Study Group?

Yoon Ga-min, listed on AniList as Ga-Min Yun, is the protagonist. He's a 178 cm high schooler at Yusung Vocational High School whose only real goal is getting into a four-year university. When no existing study group will take him, he starts his own, which is where the series gets its title. His AniList profile also lists the nickname "Crazy Glasses."

Who is Han-gyeon Lee in Study Group?

Han-gyeon Lee is Ga-min's former private tutor. Per WEBTOON's official synopsis, she enrolls at Yusung Vocational High School hoping to earn her teacher certification, which puts her back in Ga-min's orbit as a student rather than his instructor. She's one of only two characters AniList tags as a MAIN cast member, the other being Ga-min himself.

Are Ji-woo and Hyeon-u Lee related in Study Group?

Yes, they're twins, and AniList specifies Ji-woo as the elder sibling. Her character profile confirms she's a chemical engineering major, trained in Judo, and a member of the Yusong High study group. Hyeon-u's own profile is thinner: the sibling relationship and his supporting role are confirmed, but further plot detail hasn't surfaced in a source this guide could independently verify.

Who is Han-wool Phi in Study Group?

Han-wool Phi is the son of Yeonbaek Phi, a director in the White Lead Gang. That family connection makes him the cast's clearest tie to organized, gang-level pressure on Ga-min's world, rather than just a tougher classmate.

Is Study Group's cast connected to other YLAB webtoons?

Yes. AniList's relations data for Study Group lists direct ties to other YLAB titles, including Get Schooled, Hanlim Gym, To Not Die, and The World is Money and Power, plus a confirmed character-level crossover with fellow YLAB series Daejangjeon. That's the specific list behind the "Blue String Universe" label this site's review and reading guide mention.

Is there a Study Group anime with these characters?

Not yet. A theatrical 2D animated film was announced as in early development as of April 2026, with no release date confirmed since. Right now the only screen adaptation is the TVING live-action drama, which stars Hwang Min-hyun as Yoon Ga-min and has a confirmed but undated second season.

References

1. Study Group on AniList -- character database (media ID 110472) used to verify every name in this guide, including role tags and relations data
2. Study Group on WEBTOON -- official English synopsis and platform for the ongoing series
3. Jeet Kune Do on Wikipedia -- background on the martial art associated with Ga-min's fighting style in the site's existing review and reading guide