ON1 ROOKIES Season 2 Members Profile 2026: Bio, Ages & Interesting Facts
ON1 ROOKIES (온원루키즈) is a pre-debut project girl group managed by ON1 Entertainment, a Korean agency specializing in children‘s entertainment. The group was introduced through the documentary series ROONIVERSE, with the first episode released on January 12, 2024, on their official YouTube channel. Currently consisting of eight young members, ON1 ROOKIES represents a new generation of K-pop trainees being developed under a children-focused entertainment model.
ON1 ROOKIES is an eight-member pre-debut project girl group under ON1 Entertainment. Introduced through the documentary series ROONIVERSE on January 12, 2024, the group consists of Youyi, Yooran, Seojung, Jooa, Yejin, Jooha, Liya, and Seoyoon. The agency specializes in children‘s entertainment.
This article provides comprehensive profiles for each member, including verified personal information, career journeys, and interesting facts about this rising pre-debut group.
Quick Facts
Table of Contents
Who Is ON1 ROOKIES?
ON1 ROOKIES is an eight-member project girl group under ON1 Entertainment, an agency that focuses on children‘s entertainment. Unlike traditional K-pop groups that debut with a formal release, ON1 ROOKIES was introduced through the documentary series ROONIVERSE, which chronicles the members’ training and development journey.
The group is divided into two sub-units: Team A and Team B. Their pre-debut project has generated interest among K-pop fans who follow rookie groups closely, particularly because of the members‘ young ages and the agency’s unique children-entertainment focus.
The group‘s current status is pre-debut, with activities centered around content releases through their ROONIVERSE documentary series and social media presence.
Group History
Formation and Pre-Debut
ON1 ROOKIES was formed under ON1 Entertainment as a project group designed to introduce young trainees to the public before an official debut. The agency, which specializes in children’s entertainment, launched the group through the documentary series ROONIVERSE.
The first episode of ROONIVERSE was published on January 12, 2024, on the group‘s official YouTube channel. The documentary series serves as a platform to showcase the members’ training, personalities, and growth as they prepare for their eventual debut.
Pre-Debut Activities
Members were introduced gradually through the ROONIVERSE series and social media platforms. Some members, like Yejin, were introduced on Threads before appearing in the documentary. The group also released a pre-debut single, “clap,” on November 6, 2024, as part of the ON1 ROOKIES project.
Current Status
As of 2026, ON1 ROOKIES continues to operate as a pre-debut project group. The members are active through the ROONIVERSE documentary series and maintain individual Instagram accounts, building their fanbase ahead of an anticipated official debut.
Agency and Management
ON1 ROOKIES is managed by ON1 Entertainment, a Korean agency specializing in children‘s entertainment. The agency is also home to other artists, including:
- B.L.E (2021–present)
- BURVEY (2024–present), a girl group that debuted on May 1, 2020, with the song “Swing Bebe”
ON1 Entertainment manages ON1 ROOKIES as a trainee project group, with the members training under the agency while being introduced to the public through documentary content.
Member Profiles
Youyi Profile
Youyi is a member of ON1 ROOKIES and serves as the leader of Team A. She is the oldest member of the group.
Personal Information
Group Role
Youyi is the leader of Team A and a member of BURVEY.
Family Background
Youyi has an older brother named Youil (born 2008) and an older sister named Yoo Byul. Detailed family information beyond this is not publicly available.
Interesting Facts
- Her specialties include baking and rhythmic gymnastics.
- Her hobbies include drawing, cleaning, and exercising.
- Her strength is that she laughs a lot.
- She admits her weakness is that she is not good at studying.
- She misses Japanese language, culture, anime, webtoons, Japanese songs, and old K-pop idols.
- She is confident in her ability to help others without hesitation.
- She would like to travel alone.
- Her habit is that she keeps smiling.
Official Social Media
- Instagram: @iiistariii12
Yooran Profile
Yooran is a member of ON1 ROOKIES and serves as the leader of Team B.
Personal Information
Group Role
Yooran is the leader of Team B.
Official Social Media
- Instagram: @shin__yooran
Seojung Profile
Seojung is a member of ON1 ROOKIES and belongs to Team B.
Personal Information
Group Role
Seojung is a member of Team B.
Interesting Facts
- Her nickname is “개냥이” (dog-cat).
- Her main strength is her flexibility.
- Her hobbies include collecting perfumes and watching Netflix.
- Her weakness is weak physical strength.
- She misses the song “Bad Boy” by Chungha and Christopher.
- She misses playing Rummikub.
- She wants to climb the highest mountain in Korea.
- She is confident in her performance.
- Her bad habit is biting her lips.
Jooa Profile
Jooa is a member of ON1 ROOKIES and belongs to Team B.
Personal Information
Group Role
Interesting Facts
- Her specialty is cheerleading.
- Her nicknames are Jooami, Parkju, Juju, and Maichu.
- Her hobby and strength is dancing.
- Her weakness is drawing/painting.
- She misses jewel cross-stitch.
- She misses the song “Beautiful” by Wanna One.
- She is confident in her dancing.
- She wants to go on a trip with friends without parents.
- Her habit is turning her head.
Official Social Media
- Instagram: @joochaeyul_danbi
Yejin Profile
Yejin is a member of ON1 ROOKIES and belongs to Team A.
Personal Information
Group Role
Career Journey
Yejin was introduced on Threads on January 24, 2024, but she only appears in ROONIVERSE from Episode 6, released on February 16, 2024. She is also a model under 4M (4D Label model agency).
Interesting Facts
- Her hobby is listening to songs.
- Her strength is that she smiles a lot.
- Her weakness is that she is shy.
- One thing she misses is listening to old songs.
- She misses the song “Wait” by Younha.
- She is confident in her dancing skills.
- She wants to perform on a big stage.
- Her habit is tapping with her hand.
Official Social Media
- Instagram: @oxey0__
Jooha Profile
Jooha is a member of ON1 ROOKIES and belongs to Team A.
Personal Information
Note: Sources differ on Jooha’s MBTI. One source reports ESTP, while another lists IS P. This information has not been officially confirmed.
Group Role
Jooha is a member of Team A and also a member of BURVEY.
Interesting Facts
- Her nickname is “Squirrel” (다람쥐).
- Her hobby is watching dramas.
- Her strength is that she performs well when on stage.
- Her weakness is a lower ability to learn choreography.
- One thing she misses is making bead kits.
- She misses the song “Applause” by Seventeen.
- She is confident in not holding back energy on stage.
- She wants to buy a lot of clothes and wear different outfits every day.
Liya Profile
Liya is a member of ON1 ROOKIES and belongs to Team B.
Personal Information
Background and Heritage
Liya is of mixed heritage – half Russian and half Korean, with a Russian mother. She has been active as a model since childhood.
Group Role
Interesting Facts
- She first appears in Episode 2 of ROONIVERSE.
- Her nickname is Park Liya (박리아).
- Her hobby is lying down.
- Her strength is that she is pretty.
- Her weakness is that she bothers everyone.
- One thing she misses is listening to songs.
- She misses the song “Soñar”.
Official Social Media
- Instagram: liya._.pak
Seoyoon Profile
Seoyoon is the youngest member (maknae) of ON1 ROOKIES.
Personal Information
Group Role
Seoyoon is the maknae (youngest member) of ON1 ROOKIES.
Official Social Media
- Instagram: @seo_yoon0622
Discography
Pre-Debut Singles
| Song | Release Date | Notes |
|---|---|---|
| “clap” | November 6, 2024 | Pre-debut single released as part of the ON1 ROOKIES project |
Documentary Series
| Title | Release Date | Notes |
|---|---|---|
| ROONIVERSE Episode 1 | January 12, 2024 | First episode of the documentary series introducing the group |
Tours and Concerts
As a pre-debut project group, ON1 ROOKIES has not yet embarked on official tours or concerts. Their activities have primarily focused on content release through the ROONIVERSE documentary series and social media engagement.
Social Media Presence
| Platform | Official Account |
|---|---|
| Instagram (Group) | Not publicly available |
| YouTube | ON1 Entertainment / ROONIVERSE channel |
| Threads | Individual member introductions |
Individual Member Instagram Accounts:
| Member | |
|---|---|
| Youyi | @iiistariii12 |
| Yooran | @shin__yooran |
| Seojung | Not publicly available |
| Jooa | @joochaeyul_danbi |
| Yejin | @oxey0__ |
| Jooha | Not publicly available |
| Liya | liya._.pak |
| Seoyoon | @seo_yoon0622 |
20 Interesting Facts About ON1 ROOKIES
- ON1 ROOKIES is an eight-member project girl group under ON1 Entertainment, an agency specializing in children‘s entertainment.
- The group was introduced through the documentary series ROONIVERSE, with the first episode released on January 12, 2024.
- The group is divided into two sub-units: Team A and Team B.
- Youyi is the oldest member (born May 1, 2010) and Seoyoon is the youngest (born June 22, 2012).
- All members were born between 2010 and 2012, making them one of the youngest project groups in K-pop.
- Youyi is also a member of BURVEY, another girl group under ON1 Entertainment.
- Jooha is also a member of BURVEY.
- Liya is of mixed Korean and Russian heritage, with a Russian mother.
- Yejin is a model under 4M (4D Label model agency).
- Liya has been active as a model since childhood.
- The group released a pre-debut single, “clap,” on November 6, 2024.
- Yejin was introduced on Threads on January 24, 2024, before appearing in ROONIVERSE.
- Youyi‘s specialties include baking and rhythmic gymnastics.
- Jooa’s specialty is cheerleading.
- Seojung‘s nickname is “개냥이” (dog-cat).
- Jooha’s nickname is “Squirrel” (다람쥐).
- Youyi has an older brother named Youil (born 2008) and an older sister named Yoo Byul.
- Seoyoon is the maknae (youngest member) of the group.
- The group‘s current status is pre-debut, with no official debut date announced yet.
- ON1 Entertainment also manages other artists including B.L.E and BURVEY.
Frequently Asked Questions
Question: How many members does ON1 ROOKIES have?
Question: When did ON1 ROOKIES debut?
Question: Who is the oldest member of ON1 ROOKIES?
Question: Who is the youngest member of ON1 ROOKIES?
Question: What agency manages ON1 ROOKIES?
Question: What is ON1 ROOKIES’ fandom name?
Answer: This information is not publicly available.
Question: Who are the members of ON1 ROOKIES?
Question: What is Youyi‘s full name?
Answer: Youyi’s full name is not publicly available. She is known by her stage name Youyi (유이).
Conclusion
ON1 ROOKIES represents a unique approach to K-pop artist development, with ON1 Entertainment introducing young trainees to the public through documentary content before an official debut. The eight members – Youyi, Yooran, Seojung, Jooa, Yejin, Jooha, Liya, and Seoyoon – bring diverse talents and personalities to the group, from Youyi‘s leadership and baking skills to Liya’s multicultural background and Yejin‘s modeling experience.
As a pre-debut project group, ON1 ROOKIES continues to build their presence through the ROONIVERSE documentary series and social media. With members born between 2010 and 2012, they represent one of the youngest generations of K-pop trainees currently active. Their journey from pre-debut project to official debut will be one to watch for fans of rookie K-pop groups.
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