SeoAh (Hangul: 서아) is a South Korean idol and the 23rd revealed member of tripleS. She was revealed as S23 on April 3, 2024.
SeoAh made her debut on May 8, 2024, with tripleS' first studio album, ASSEMBLE24, and the title track, “Girls Never Die”. She made her official sub-unit debut in tripleS' seventh sub-unit, Glow, with their digital single, “Inner Dance”.
She is a member of the sub-unit, Glow.
History[]
Early life[]
SeoAh was born as Jeong Hae-rin (정해린) on June 11, 2010 in Buk-gu, Gwangju Metropolitan City, South Korea.
2024: Reveal & Debut[]
On March 21, Blind Double Class Objekts were announced for the last remaining members. Fans were able to purchase a DCO of each small s's handwriting from the 21st to 24th, that would later turn into an objekt of the member when they were revealed.[1] On March 24, SIGNAL #485 was released, confirming S21-24 had already met with the twenty other members on March 18 at the Gapyeong HAUS, and were already working together for the upcoming OT24 debut.
On March 27, S23's teaser drop was released.[2] On April 3, Jeong HaeRin was announced as the group's 23rd member through her introductory video.[3] On the same day, it was announced that a gravity would take place to determine her stage name, as her name held the same pronunciation as HyeRin's in Korean.[4] On April 4, a sweet has confirmed that HaeRin is the newest and final maknae of the group.[5] On April 6, HaeRin's stage name was determined as 'SeoAh' through the S23 Stage Name Event Gravity.
On April 16, SeoAh's concept photo for ASSEMBLE24 was released.[6]
On May 8, she made her official debut with tripleS first studio album, ASSEMBLE24, and the title track, “Girls Never Die”.
On June 21, she debuted with tripleS' eighth sub-unit, Glow, with the digital single, "Inner Dance".
2025: tripleS Come True Tour, ASSEMBLE25, neptune debut[]
From January 11 to March 30, SeoAh participated in the tripleS Come True tour, together with SeoYeon, NaKyoung, DaHyun, Nien, JooBin, HaYeon, and Sullin.
On May 12, she made her comeback with tripleS' second studio album, ASSEMBLE25, and the title track, "깨어 (Are You Alive)".
On September 9, she was determined as a member of the sub-unit Neptune, through the msnz Grand Gravity. She debuted with this subunit on November 24 with the single "Fly Up" from the mini-album Beyond Beauty.
Discography Participation[]
Studio Albums[]
- [2024.05.08] ASSEMBLE24
- [2025.05.12] ASSEMBLE25
Mini Albums[]
- [2025.11.24] Beyond Beauty - neptune
Digital Singles[]
- [2024.06.21] Inner Dance — Glow
- [2024.07.20] Hash
Filmography[]
| Year | Name | Network | Role |
|---|---|---|---|
| 2024 | Strong Girl: Badge War Season 2 | 1theK Originals YouTube Channel | Herself |
| 2025 | The Spring Vacation of NXT & Glow | tripleS Official YouTube Channel | Herself |
| Strong Girl: Badge War Season 3 | 1theK Originals YouTube Channel | Herself |
