GLACIA Members: Complete Profile, Pre-Debut History & What Happened to the Group
GLACIA (글레이시아) was a South Korean pre-debut girl-group project that never reached an officially documented debut. The surviving public record describes GLACIA as a four-member team and identifies three members by name: Nene, Lee Yunseon and Baek Yeonsoo. A fourth member remains unidentified in the available record.
Unlike a conventional K-pop group, GLACIA left behind very little verifiable documentation. There is no reliable public record locating an official debut release, fandom name, agency announcement, formal debut date or confirmed disbandment statement. The most useful development in tracing the group’s history is what happened to two of its named members: Lee Yunseon and Baek Yeonsoo later became members of S2iT, a Monster Brain-backed girl group that officially debuted in 2026. Monster Brain’s own artist page currently lists both among S2iT’s five members.
This makes GLACIA better understood as a pre-debut project that became inactive before an official debut, rather than as a conventional debuted idol group with a documented discography.
Quick Overview
| Field | Verified information |
|---|---|
| Group | GLACIA (글레이시아) |
| Group type | Pre-debut South Korean girl group |
| Documented lineup | Four members in the surviving profile record |
| Publicly identified members | Nene, Lee Yunseon, Baek Yeonsoo |
| Fourth member | Unidentified in the available public record |
| Agency | Not publicly verified |
| Official debut date | No verified debut found |
| Debut release | None located |
| Fandom name | Not officially confirmed |
| Official group color | Not officially confirmed |
| Discography | No GLACIA release located |
| Formal disbandment announcement | Not located |
| Last documented activity | Public profile evidence places the group’s known activity in or before 2025 |
| Later connection | Lee Yunseon and Baek Yeonsoo became S2iT members |
| Official GLACIA website | Not located |
| Official GLACIA social accounts | Not independently verified |
The four-member classification and the identities of the three named members come from the surviving GLACIA profile record; the lack of an official debut, agency and fourth-member identification could not be resolved through stronger sources.
Table of Contents
Who Was GLACIA?
GLACIA appears to have been a pre-debut girl-group lineup rather than a formally debuted K-pop act. The available profile record identifies four members but provides little information about the organization behind the project. No agency announcement or official artist page for GLACIA was located during this research.
That absence matters. K-pop database pages often preserve trainee and pre-debut lineups long after their original projects disappear, but a profile entry by itself does not establish that a group officially debuted or that its members held officially assigned positions. For GLACIA, the public record is especially fragmentary: even the surviving profile lists three named members and simply marks the fourth as “?”.
The strongest independently verifiable thread begins after GLACIA. Lee Yunseon and Baek Yeonsoo were later associated with S2iT, a five-member girl group under Monster Brain. The agency’s own website currently lists S2iT and names Yunseon under the stage name Haru, alongside Yeonsoo, Seungbi, Hyobin and Sea.
That later connection gives GLACIA’s story a useful context: at least two members continued pursuing idol careers rather than disappearing completely from the public music industry.
How Was GLACIA Formed?
There is currently no reliable public chronology establishing when GLACIA was formed, which company created the group, or whether the lineup went through a formal trainee program.
The available GLACIA profile identifies the project as a four-member South Korean pre-debut group but does not provide a formation announcement, trainee-show history, debut schedule or agency record.
For that reason, it would be misleading to describe GLACIA as an agency-created group of a particular company or to give a specific formation year without stronger evidence.
What can be established is that two GLACIA members subsequently entered the documented pre-debut lineup of S2iT in 2025. A September 19, 2025 report from Media Defense described S2iT as a five-member Monster Brain group consisting of Yunseon, Yeonsoo, Jiwoo, Hyobin and Seungbi, with Yunseon serving as the leader.
In other words, GLACIA’s surviving record is best treated as a piece of the members’ pre-debut histories, not as a conventional group biography.
Official Debut
GLACIA does not have a verified official debut date or debut release.
No official GLACIA music release was located in the music databases and public sources checked for this article. The available profile record explicitly describes the team as pre-debut, which is consistent with the absence of an identifiable single, EP, album or official debut-stage record.
That distinction is important because a pre-debut group can have photographs, trainee activities, public appearances or prospective members without ever becoming an officially debuted idol group.
There is also no verified GLACIA fandom name, official color or official debut greeting supported by a primary source.
GLACIA Members
The surviving record identifies three members and leaves the fourth unidentified.
| Member | Full/Stage Name | GLACIA Role | Birth Date | Nationality | Verified Notes |
|---|---|---|---|---|---|
| Nene | Nene (네네) | Not documented | March 2004 | Japanese | Public profile record says she studied in South Korea in a practical-music program |
| Lee Yunseon | Lee Yunseon (이윤선) | Not documented | July 14, 2005 | Korean | Later became Haru of S2iT |
| Baek Yeonsoo | Baek Yeonsoo (백연수) | Not documented | June 25, 2005 | Korean | Later became Yeonsoo of S2iT |
| Unidentified member | Not publicly identified | Not documented | Not publicly available | Not publicly available | The surviving profile record contains no usable name or biographical information |
The GLACIA source does not document positions for any of the members, so roles such as main vocal, main dancer or rapper should not be retroactively assigned to the group.
Nene
Stage name: Nene (네네)
Birth: March 2004
Nationality: Japanese
GLACIA role: Not publicly documented
Nene is one of the few GLACIA members for whom a stage name and nationality survive in the public record. The available profile identifies her as Japanese and gives her birth month as March 2004, but does not provide a birth day, full birth name or official GLACIA position.
The same source says Nene was studying abroad in South Korea at a university in a practical-music department. Because this information comes from a secondary profile rather than an official university or agency source, it should be treated as reported rather than independently confirmed.
There is currently not enough evidence to establish what happened to Nene after the GLACIA project became inactive. Her subsequent professional activities could not be reliably connected to an official entertainment-company record during this research.
Lee Yunseon
Stage/name recorded for GLACIA: Lee Yunseon (이윤선)
Birth: July 14, 2005
Nationality: Korean
GLACIA role: Not publicly documented
Later stage name: Haru
Current group: S2iT
Lee Yunseon has the clearest publicly traceable career path of the former GLACIA members. The surviving GLACIA record identifies her as a South Korean born on July 14, 2005 and notes her background in dance.
Her later career provides much stronger documentation. She became Haru in S2iT, a group under Monster Brain, and debuted with the team on March 14, 2026. Contemporary coverage from Media Defense identified Yunseon as part of S2iT’s five-member pre-debut lineup in September 2025.
Monster Brain’s official artist listing now includes Haru among S2iT’s five members, confirming that her idol career progressed beyond the GLACIA project.
Secondary biographical sources also document Yunseon’s long-standing dance background, including participation in dance activities before her S2iT debut.
The most significant point for a GLACIA profile is therefore not an undocumented GLACIA position but the career continuity: Yunseon moved from an unreleased pre-debut project into a formally debuted group.
Baek Yeonsoo
Stage/name recorded for GLACIA: Baek Yeonsoo (백연수)
Birth: June 25, 2005
Nationality: Korean
GLACIA role: Not publicly documented
Current stage name: Yeonsoo
Current group: S2iT
Baek Yeonsoo is the other GLACIA member whose later career can be independently traced. The surviving profile record gives her birthday as June 25, 2005 and identifies her as Korean.
She subsequently joined S2iT’s pre-debut lineup at Monster Brain. A September 2025 report identified Yeonsoo and Yunseon among the group’s members before their eventual debut.
Monster Brain’s official S2iT artist page now lists YEON SOO alongside Haru, Seungbi, Hyobin and Se-a.
Yeonsoo’s later debut gives GLACIA an unusual historical relevance: although GLACIA itself never developed into a documented recording act, at least one part of its trainee-era lineup continued into a fully launched group.
Secondary sources additionally record Yeonsoo’s training and audition background, including dance and vocal study. Those details should be treated as supporting biography rather than evidence about GLACIA itself.
The Unidentified Fourth Member
The fourth GLACIA member is not publicly identified in the surviving source record examined for this article.
The available profile literally leaves the member’s stage name, birth name, birthday, nationality and position blank.
This is precisely the kind of gap that should not be filled with an internet guess. No reliable source located during this research established who the fourth member was or whether she later joined another group.
Until stronger evidence emerges, KpopBio.com should list the fourth member as unidentified, rather than assign a name based on fan speculation or an unsupported database entry.
Career Timeline
Because GLACIA never produced a well-documented debut, its timeline is more accurately a chronology of the surviving evidence than a conventional release history.
| Date | Development | Verification |
|---|---|---|
| Pre-2025 | GLACIA existed as a four-member pre-debut girl-group project | Secondary profile record |
| 2025 | Publicly documented GLACIA activity appears to cease; no formal disbandment announcement located | Secondary profile record; absence of subsequent GLACIA activity |
| September 19, 2025 | Media Defense reports S2iT’s five-member pre-debut lineup, including Yunseon and Yeonsoo | Reputable Korean local publication |
| November 2025 | Yunseon and Yeonsoo were formally introduced among the S2iT lineup under their later identities | S2iT-related secondary records |
| March 14, 2026 | S2iT officially debuts with “What I Want” | Music/distributor records |
| August 13, 2026 | S2iT releases “Blue Summer” | Genie/Bugs; Korean media |
| September 2026 | Monster Brain continues to list S2iT as an active artist, with Haru and Yeonsoo in the five-member lineup | Official Monster Brain website |
The S2iT connection is the most important chronological development because it transforms two otherwise incomplete GLACIA biographies into traceable professional careers.
Music and Major Releases
GLACIA Discography
No official GLACIA release was located.
The available evidence does not support listing a debut single, pre-release, EP or album under GLACIA. It is therefore preferable to leave the discography empty rather than populate it with songs belonging to other artists or to S2iT.
The Later S2iT Connection
The later careers of Yunseon and Yeonsoo provide a useful point of comparison.
| Release | Artist | Type | Release Date | Relevance |
|---|---|---|---|---|
| “What I Want” | S2iT | Digital single | March 14, 2026 | Official debut release of Haru and Yeonsoo’s later group |
| “Blue Summer” | S2iT | Single | August 13, 2026 | Latest verified S2iT release at the time of this review |
Bugs lists “What I Want” as a two-track single released on March 14, 2026 by Monster Brain and distributed through Genie Music.
“Blue Summer” followed on August 13, 2026. Genie and Bugs both identify Monster Brain as the planning/agency company and list the release date as August 13.
The significance for GLACIA is historical rather than discographical: the group’s public legacy currently survives chiefly through members who continued into another group.
Major Achievements
GLACIA itself has no verified chart, award, sales or music-show achievements because no official debut or commercial release has been established.
It would therefore be inaccurate to assign achievements from S2iT directly to GLACIA.
The meaningful career milestone connected to former GLACIA members is their later participation in S2iT. That group formally debuted on March 14, 2026 with “What I Want,” and released “Blue Summer” on August 13, 2026.
This distinction matters for historical accuracy: S2iT’s achievements belong to S2iT, not to GLACIA.
Latest Verified Updates
As of September 6, 2026, there is no newly announced GLACIA reunion, relaunch or official archival project that could be verified through a primary source.
The important current development concerns former GLACIA members Haru (Lee Yunseon) and Yeonsoo (Baek Yeonsoo). They are active members of S2iT, whose agency Monster Brain currently lists the group on its official artist roster.
S2iT’s latest verified release is “Blue Summer,” released August 13, 2026. CBS NoCut News reported that Monster Brain planned a September 7 showcase and subsequent broadcast activity around the comeback.
For GLACIA itself, however, the current status remains best described as inactive/pre-debut and apparently discontinued, without a publicly located formal disbandment announcement.
What We Verified
The following points can be supported with the available evidence:
- GLACIA was documented as a four-member South Korean pre-debut girl group.
- Three members are publicly identified: Nene, Lee Yunseon and Baek Yeonsoo.
- No GLACIA debut release or official debut date was located.
- No verified official agency for GLACIA was located.
- Lee Yunseon later became Haru of S2iT.
- Baek Yeonsoo later became a member of S2iT.
- S2iT officially debuted on March 14, 2026 with “What I Want.”
- S2iT released “Blue Summer” on August 13, 2026.
What Is Not Officially Confirmed
Several commonly expected profile details remain unavailable:
- GLACIA’s agency
- exact formation date
- official debut date
- debut song or album
- official fandom name
- official group color
- official GLACIA positions for the members
- identity of the fourth member
- date of a formal disbandment announcement
- post-GLACIA career of Nene
The most responsible editorial treatment is to mark these as unavailable rather than infer them from unrelated databases or later careers.
Official Accounts and Sources
No verifiable official GLACIA website or active official GLACIA social-media account was located during this research.
For readers interested in the two former GLACIA members whose careers continued, Monster Brain’s official artist page provides the strongest current source for S2iT. It lists Yeon Soo, Seung Bi, Haru, Hyo Bin and Se A as the group’s members and provides the group’s official social accounts.
Official related source: Monster Brain – S2iT official artist listing
Sources & References
Primary Sources
Monster Brain – S2iT artist profile. The agency’s official website lists S2iT as an artist and identifies the five-member lineup, including Haru and Yeon Soo.
Monster Brain – official website. The company website currently features S2iT and related official video material.
Music and Release Sources
Bugs – “What I Want.” Official Korean music-database information records the March 14, 2026 single release, title track and Monster Brain as the planning company.
Genie – “Blue Summer.” Records the August 13, 2026 release and Monster Brain as the planning company.
Bugs – “Blue Summer.” Confirms the August 13, 2026 release date and two-track single format.
Reputable News / Interviews
Media Defense – September 19, 2025. Reports the pre-debut S2iT lineup, its Monster Brain connection and Yunseon’s role as leader.
CBS NoCut News – August 13, 2026. Reports S2iT’s “Blue Summer” comeback and September 7 showcase plans.
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