Seoho

Status: Active group member and solo artistYears active: 2019–present with ONEUS; solo 2025–present

Seoho in the official “Hatchling” music video, stored locally by CVM Sekai.

Seoho is ONEUS’s bright, high-powered main vocalist and a solo artist whose first official single, “Hatchling,” arrived on March 23, 2025. This is his one canonical profile for both the Members and Artists directories.

Profile

Stage name	Seoho (서호)
Birth name	Lee Seo-ho (이서호)
Born	June 7, 1996
Nationality	South Korean
Group	ONEUS
Role	Main vocalist
Solo debut	March 23, 2025
Solo debut release	“Hatchling”

1. Before ONEUS

Before debut, Seoho competed on Produce 101 Season 2 in 2017 and later appeared on MIXNINE. Those programs introduced him as a trainee, but the more important long-term result was the experience: repeated live evaluations, different team arrangements and the uncomfortable art of learning while an audience keeps score.

He trained under RBW and appeared through the RBW Boyz project before the company finalized ONEUS. By debut, the clean upper register that had been a survival-show asset had become one of the group’s defining sounds.

2. ONEUS career

ONEUS debuted on January 9, 2019 with the EP Light Us and its title track “Valkyrie.” Seoho became the group’s main vocal engine, often carrying the lift into a chorus or the climactic line that turns a theatrical arrangement into an actual emotional payoff.

His role is not limited to standing still and singing the difficult note. Seoho’s acrobatics and dance work make him unusually physical for a main vocalist, while his comic timing keeps the elegant stage image from becoming too tidy. Across ONEUS releases, he has also contributed to lyrics and composition, making the music itself part of the profile rather than treating him as only the person assigned to deliver it.

3. Solo career

RBW announced Seoho’s first solo single, “Hatchling,” in March 2025. The official music video and digital single were released on March 23 through ONEUS’s official channels. The release followed a performance of the song at ONEUS’s Seoul concert and arrived as a gift for fans during his military-service period.

“Hatchling” leans into warmth and playfulness instead of trying to manufacture a grim, prestige-soloist transformation. That choice fits him. The song gives his bright vocal color room to lead while keeping the slightly mischievous energy fans associate with him. It is an official single with its own music video and artist credit, so Seoho belongs in Artists as well as Members.

4. Voice and performance

Seoho’s upper register is clear without losing body, which lets him cut through dense ONEUS production without sounding disconnected from the rest of the arrangement. He can handle sustained theatrical lines, quick melodic turns and lighter phrasing, then move straight into choreography or an acrobatic element. The combination makes him valuable not only as a singer but as a stage problem-solver.

Offstage, the precision gives way to chaos more quickly than the elegant photos suggest. That contrast is part of the appeal: the person casually causing trouble in group content is also the singer trusted with the note holding the entire final chorus together.

5. Solo discography

Singles

“Hatchling” (2025)

6. RaeRae’s take

Some solo releases arrive wearing a black turtleneck and demanding to be called art. Seoho gave us “Hatchling,” which feels much more honest for the man in question. It is bright, nimble and just odd enough around the edges to remind you that ONEUS’s reliable high-note machine is also one unattended microphone away from becoming everybody’s problem. Excellent. Keep both versions.

YouTube tracking history

Official videos tracked for this artist. Current and cumulative view history is collected by CVM Sekai.