SeoYeon윤서연

Before MODHAUS

No trainee period. Contestant on Queendom Puzzle (24th).

Notes

• First member revealed; the calendar of tripleS starts with her.
• Chungnam Girls' High School graduate; originally preparing a college retake.
• Queendom Puzzle contestant with Lee JiWoo.
• Known inside the HAUS as a game-sharp, warm unnie presence.
• Winter cover, Team Blue C — sun and neptune. Song: Merry & Happy. Official 24 Sep 2026.
• Objekt colour Dodger Blue — white SIGNAL, blue stamp.
• Appeared in Badge War Seasons 1 and 2 — results stay on the Badge War page.
• ASSEMBLE25 leader for 깨어 (Are You Alive).
• HAUS nickname Hamham.

How she was batched

• Universe 1 · supporting Plus

  Acid first. Crystal as the plus.

  The first Grand Gravity did not pick eight friends. It picked four — Acid Angel from Asia — and left the other four of S1–S8 standing as the remainder. That remainder is +(KR)ystal Eyes: the plus, the crystal counterpart, SeoYeon captaining JiWoo, ChaeYeon and SooMin. AAA got Generation, the first MV, iTunes US K-pop #1, the acid temperature. KRE got Cherry Talk and a delayed official video. The plot was never “AAA is the group.” The plot was two mirrored fours of the same eight, filmed in the same HAUS, then crashed together as ACID EYES / Cherry Gene. Supporting Plus meant keeping the crystal four on camera while the acid four had the title. SIGNAL did that work. Gravity did the split. The collision was the thesis.

• Two Big WAVes

  LOVE spelled backwards is EVOL.

  Universe 2 split the growing roster into a love-side eight and a harder eight. SeoYeon kept the captaincy through MUHAN and the Authentic US tour. YooYeon took EVOL through MUJUK and Australia. Girls’ Capitalism vs Invincible is not a rivalry chart — it is a palindrome. The content team ran two touring DIMENSIONs at once: two HAUS temperatures, two title-track bodies, one fandom name. That is the first time 24 started to feel like a system instead of a countdown.

• msnz · four planets

  Moon, Sun, Neptune, Zenith — six each.

  WAV named the 2025 OT24 umbrella Magic Shine New Zone, then the roster split into four 6-member planets on one record, Beyond Beauty. Sullin’s Moon, Xinyu’s Sun (Bubble Gum Girl), SeoYeon’s Neptune, HaYeon’s Zenith. Team dynamic: four captains, four temperatures, monthly Japanese originals toward 2027. Sun is the aero-pop flag this archive had been skipping; the other three planets are the rest of the sky.

Group albums she stood on

• 2023-02-13 · Mini album · KR

  ASSEMBLE

  tripleS (S1–S10) · Rising

  Ten-member debut. Rising chosen from COSMO Hub. Circle #6, ~55k. Official MV on @triplescosmos.

  1. 01Beam
  2. 02Before the Rise
  3. 03RisingTitle · Gravity
  4. 04ColorfulPromoted b-side
  5. 05The Baddest
  6. 06New Look
  7. 07초월 (Chowall)

• 2024-05-08 · Studio album · KR

  ASSEMBLE24

  tripleS · Girls Never Die

  OT24 first studio album. Circle #3, 211k+. Official MV on @triplescosmos.

  1. 01S
  2. 02Girls Never DieTitle
  3. 03가시권 (Heart Raider)
  4. 04Midnight Flower
  5. 05White Soul Sneakers
  6. 06치유 (Chiyu)
  7. 0724
  8. 08이면의 이면 (Beyond the Beyond)
  9. 09Non Scale
  10. 10Dimension

• 2024-07-20 · Digital single · JP

  ###

  tripleS · ###

  Japan pre-debut single. Read ‘hash’. First SME-facing stamp before Untitled.

  1. 01###Title · read ‘hash’

• 2025-04-12 · Digital single · JP

  Girls Never Die (Japanese Ver.)

  tripleS · Girls Never Die (Japanese Ver.)

  Japanese version of the ASSEMBLE24 title. Later collected on SecretHimitsuBimil CD.

  1. 01Girls Never Die (Japanese Ver.)Title

• 2025-05-12 · Studio album · KR

  ASSEMBLE25

  tripleS · 깨어 (Are You Alive)

  OT24 year-two. Circle #3, 461k, KMCA Platinum. Title by Gravity. Persona and Diablo with Park SoHyun.

  1. 01@% (Alpha Percent)
  2. 02깨어 (Are You Alive)Title · Gravity
  3. 03추리소설 (Detective Soseol)Promoted b-side
  4. 04어제 우리 불꽃놀이 (Firework Diary)
  5. 05Love Child
  6. 06PersonaPark SoHyun
  7. 07Too Hot
  8. 08DiabloPark SoHyun
  9. 09Friend Zone
  10. 10Love2Love

• 2026-06-01 · Mini album · KR

  ASSEMBLE26 <LOVE&POP> pt.1

  tripleS · Baby Flower

  First of three LOVE&POP parts. Circle #2, 518k, KMCA Platinum. Official MV on @triplescosmos. Pt.2 is 16 Oct 2026, 13:00 KST. Pt.3 January 2027.

  1. 01Sad Girls Schemin'
  2. 02Peer
  3. 03Baby FlowerTitle
  4. 04Type of Girl
  5. 05Sleek
  6. 06I Like That
  7. 07Me Myself Mode

• 2026-06-03 · Digital single · JP

  Baby Flower (Japanese Ver.)

  tripleS · Baby Flower (Japanese Ver.)

  Japanese version of the LOVE&POP pt.1 title. Official audio on @triplescosmos.

  1. 01Baby Flower (Japanese Ver.)Title

Her clock

1. Sun 1 May 2022 · Reveal

   S1 Yoon SeoYeon

   First member. A Daejeon vocalist. Official anniversary date of tripleS. Teaser: YoonSeoYeon.SSS.

2. Thu 4 May 2023 · Dimension

   +(KR)ystal Eyes — Aesthetic

   SeoYeon, JiWoo, ChaeYeon, SooMin. Cherry Talk. The crystal counterpart to Acid Angel.

3. Thu 17 Aug 2023 · Dimension

   LOVElution — ↀ MUHAN

   Girls' Capitalism. SeoYeon captains the love-side eight. Authentic US tour follows.

4. Sun 24 Dec 2023 · Reveal

   S20 Park ShiOn

   From Daejeon, like SeoYeon. Closes the first twenty on Christmas Eve. Later pre-selected for ∞!. Teaser: ParkShiOn.SSS.

Tours & rooms she walked

• Sep–Oct 2023 · United States · Tour

  Authentic — LOVElution

  First overseas tour, September–October 2023. LOVElution carried the Authentic United States leg. It is the first of three Authentic runs: this US leg, Australia with EVOLution on 20–23 December 2023, then Seoul on 3–4 February 2024. This page is the archive note for the US leg only. Cities inside the country are not listed here, and this archive does not sell tickets.

• 20–23 Dec 2023 · Australia · Tour

  Authentic — EVOLution

  20–23 December 2023 in Australia. EVOLution took the second Authentic leg, after LOVElution’s United States run in September–October 2023 and before Authentic in Seoul on 3–4 February 2024. This page records that Australia leg. It does not sell tickets.

• 3–4 Feb 2024 · Seoul · Concert

  Authentic in Seoul

  3–4 February 2024 in Seoul, the last Authentic run. Night one was LOVElution and EVOLution. Night two was all 20 members revealed by then. ASSEMBLE24 was announced from that stage. The US leg was September–October 2023 and the Australia leg was 20–23 December 2023. This archive does not sell tickets.

• 2026 · Asia · Asia tour

  My Secret New Zone

  First Asia tour under the msnz banner, 2026. Performance Gravity chose each unit’s songs. msnz is the OT24 umbrella that split into Moon, Sun, Neptune, and Zenith. This page is the tour note, separate from the dimension page and from ANDLESS. This archive does not sell tickets.

Same orbit

• S10DaHyunplanet
• S7NaKyoungplanet
• S13Nienplanet
• S11Kotoneplanet
• S23SeoAhplanet