SeoAh

Who Is SeoAh?

SeoAh (서아), born Jeong Ha-erin (정해린) on June 11, 2010, is the maknae and a vocalist of tripleS, MODHAUS’s boundary-pushing 24-member K-pop girl group built around fan participation. As the group’s youngest member, SeoAh has quickly become one of its most talked-about faces — proof that tripleS and its fandom WAV keep finding fresh talent even years into the project.

From Gwangju to tripleS’s Final Lineup

Before joining MODHAUS, SeoAh trained in dance and vocals at Joy Dance Music Academy in Mokpo and practiced taekwondo growing up in Gwangju, South Korea. She was revealed as tripleS’s twenty-third member — S23 — on April 3, 2024, one of the final four additions that completed the group’s full 24-member roster. Interestingly, a special “Gravity” event was held just to decide her stage name, since her birth name closely resembled fellow member Jeong HyeRin’s.

Debuting as tripleS’s New Maknae

SeoAh debuted alongside all 24 members on May 8, 2024, with the studio album ASSEMBLE24 and its title track “Girls Never Die,” instantly becoming tripleS’s new youngest member. The following month, she stepped into her first sub-unit spotlight with Glow, tripleS’s eighth sub-unit, on the digital single “Inner Dance.” She later joined the sub-unit Neptune as part of the group’s late-2025 msnz sub-unit universe and its mini album Beyond Beauty.

The Group’s “Counseling Center”

Despite being nearly a decade younger than tripleS’s oldest member, SeoAh has earned a reputation among her groupmates as wise beyond her years — so much so that they nicknamed her “Counseling Center” for how often they turn to her for advice. Friends describe her as hard-working, kind, confident, and mature, and her sunny nickname and light-cyan representative color reflect that same warm, grounded personality.

Life Off Stage

When she’s not promoting with tripleS, SeoAh enjoys reading, drawing, exercising, and gaming, and she’s a big fan of the KIA Tigers baseball team. Her favorite foods include ramen, mango, tteokbokki, gopchang, and fried kimchi, and she has a well-known love of tanghulu. She’d love to try skydiving one day, and despite years of watching horror movies, she says she isn’t scared of them anymore — she insists the plots are always predictable.

Quick Facts About SeoAh

As the baby of tripleS’s massive lineup, SeoAh is only just getting started — and both her groupmates and WAV are excited to watch her grow alongside the group.