Kep1er Becomes a Six-Member Group as Seo Youngeun Officially Departs

Seven months. That is how long WAKEONE Entertainment and KLAP Entertainment held out hope that Seo Youngeun (서영은) could recover and return. On March 6, 2026 KST, they stopped waiting. The agencies released a joint statement confirming Youngeun’s permanent departure from Kep1er (케플러), closing the chapter on the group’s original lineup and opening a new one as a six-member act.

What Happened

Youngeun had been on hiatus since July 2025, sidelined by health issues that her agencies described as requiring “sufficient time to rest and recover.” The group carried on as seven for that period, releasing content and maintaining their schedule without her. After seven months, her medical situation made a return untenable.

The agencies released this statement on March 6:

“Kep1er will continue its activities as a six-member group, consisting of Choi Yujin, Xiaoting, Kim Chaehyun, Kim Dayeon, Hikaru, and Huening Bahiyyih. Seo Youngeun, who has been part of Kep1er’s precious journey since their debut in 2022, will conclude her activities with the group. We wish Youngeun all the best in her future endeavors.”

The Third Exit in Kep1er’s Four-Year Run

This is not the first time Kep1er has lost a member, but it is the third, and that number carries weight. The group launched in January 2022 as nine members, all formed through CJ ENM’s Mnet reality competition Girls Planet 999. Youngeun finished 5th on the show, one of the stronger results in a cast that pulled from Korean, Chinese, and Japanese trainees.

The first lineup change came in July 2024, when Kang Ye-seo and Sakamoto Mashiro departed together. The group reshuffled as seven and released their first full-length Korean studio album, Kep1going On, in June 2024, just before those departures. They followed with the TIPI-TAP mini album in November 2024, their most recent release.

Who Remains

The six members carrying Kep1er forward are leader Choi Yu-jin, Shen Xiaoting, Kim Chae-hyun, Kim Da-yeon, Ezaki Hikaru, and Huening Bahiyyih. The lineup represents a mix of nationalities consistent with the group’s origins as a multinational act: Korean, Chinese, and Japanese members, with Huening Bahiyyih also holding American roots as the sister of TXT’s Huening Kai.

What Comes Next

The six-member Kep1er has not announced a comeback date as of this report. Their most recent material, TIPI-TAP, dropped in November 2024 and served as their sixth mini album. With the lineup now settled, a new era is the logical next step. The group has consistently delivered music and performances through every prior transition, and there is no reason to expect that changes now.

For Youngeun, the agencies signaled a quiet and respectful exit with no door closed on a future in entertainment, just not within Kep1er. Her health remains the priority.