H1-Key

H1-Key (read as High-key; stylized as H1-KEY) is a South Korean girl group formed and managed by Grandline Group (GLG) and Sony Music Korea. The group is composed of four members: Seoi, Riina, Hwiseo and Yel. Sitala left the group on May 25, 2022, and Hwiseo was introduced as a new member, replacing Sitala on June 14, 2022. They made their debut with the release of their first single album, Athletic Girl, on January 5, 2022.

Name
Their group name H1-Key is pronounced and inspired by the word "High Key" and the aim for "confident" and "healthy beauty".

Pre-debut activities and introductions
Yel was a trainee under JYP Entertainment. Riina was previously training under WM Entertainment. Sitala, daughter of the late Thai actor, singer and producer Sarunyoo Wongkrachang, was a trainee under Lionheart Entertainment. Seoi was a trainee under YG Entertainment.

On November 18, 2021, Naver News revealed that Grandline Group (GLG), the newly-established sub-label of the now defunct hip-hop based label Grandline Entertainment (GRDL), were planning to debut a new girl group on January 5, 2022. On November 20, 2021, the group opened their official social media accounts.

On November 23, 2021, Yel was announced as the group's first member through a self-choreographed cover video of "Bad Habits" by Ed Sheeran. On November 26, 2021, Seoi was introduced as the group's second member. On November 29, Riina, a former Produce 48 contestant and WM Ggumnamu member, was revealed as the third member. On November 30, Sitala was introduced as the group's fourth member. Later the members made their first full group appearance in a dance cover video for the song "Me So Bad".

Controversy around Sitala
When GLG unveiled the group's Thai member Sitala in November 2021, various K-pop fans in Thailand called for her removal, as her late father was a known supporter of the People's Alliance for Democracy, a military tyranny that ousted two democratic-elected civilian governments in the 2006 and 2014 military coup d'états. In response to the backlash, GLG issued a statement on December 8 saying that Sitala cannot be held responsible for her father's actions, which do not reflect her individual merits or political views.

2021–2022: Debut with Athletic Girl, Sitala's departure and Run
On December 21, 2021, it was announced via social media that the group make their debut with their first single album, Athletic Girl, with the title track of the same name. Prior to the release, it was announced that the group would be partnering with Sony Music for international promotions.

The album was released on January 5, 2022. They held a press showcase for the album on the same day. H1-Key made their broadcast debut on January 7, at KBS2's Music Bank.

On May 25, GLG announced that Sitala had left the group due to personal circumstances.

On June 7, it was announced that the quartet would be releasing their first maxi single album titled Run on July 6, with the addition of a new member, Hwiseo. On December 6, H1-Key confirmed their comeback on January 5, 2023, the anniversary of their debut.

2023–present: Rose Blossom, Seoul Dreaming, H1-Keynote Project and Love or Hate
On January 5, the quartet released their first extended play titled Rose Blossom, with the title track of the same name.

In June 2023, members Riina and Hwiseo were participants in the Mnet girl group survival show Queendom Puzzle. Riina was eliminated in the second elimination round in episode 9, while Hwiseo finished in first place, debuting in the female supergroup El7z Up.

The group released their second extended play Seoul Dreaming on August 30, led by the title track "Seoul (Such a Beautiful City)". The single "Time to Shine", a pre-release of the EP, was released on August 23. The group subsequently took their first music show win on The Show on September 5.

The group would launch a music project titled H1-Keynote, beginning with the release of the digital single "Thinkin' About You" on January 19, 2024, followed by the second digital single of the project "Deeper" on February 27.

The group released their third extended play Love or Hate on June 19, 2024.

Current

 * Seoi (서이) – leader, vocalist
 * Riina (리이나) – vocalist
 * Yel (옐) – vocalist, rapper
 * Hwiseo (휘서) – vocalist, rapper

Former

 * Sitala (시탈라) – rapper, vocalist