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Being a part of sub-units formed by the respective group of an idol is common. But it is unusual for idols to be a part of a group composed of idols from various K-Pop groups. There are many idols who are a part of two or more groups. There are numerous such groups, ranging from duos to groups with a large number of members. Though some of those groups aren't active now, they aren't even officially disbanded.
Here are some of the idols who are a part of multiple groups.
Mark Lee
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Boy band NCT from SM Entertainment has four sub-units. Mark Lee, a member of NCT, is a part of NCT 127, NCT U, and NCT Dream, three of the group's sub-units. The rapper of NCT is also a member of the male supergroup formed by SM Entertainment called SuperM.
Lee Tae-yong
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Taeyong is a member of SM entertainment’s boy group NCT. He belongs to two sub-units of the group NCT U and NCT 127. The leader of the Seoul-based sub-unit NCT 127 is also a part of the SM’s Supergroup SuperM.
Ten
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Ten is a Thai member of NCT and its sub-units NCT U and WayV. The vocalist and dancer of NCT is also a part of SM The Performance and SuperM, the supergroup formed by his agency.
Lucas
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Lucas is a member of SM’s boy band NCT and its Chinese sub-unit WayV, and rotational sub-unit NCT U. The Hong Kong rapper is also a part of the supergroup SuperM.
Karina
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Karina is the leader, rapper, and dancer of SM’s youngest girl group AESPA. She is a member of the recently created female supergroup GOT the Beat by SM entertainment in addition to AESPA.
Winter
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Along with bandmate Karina, AESPA’s vocalist Winter is also a member of the supergroup GOT the Beat which is the first sub-unit of the project “Girls On Top.”
Taeyeon
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Taeyeon is the leader and main vocalist of SM Entertainment’s girl group, Girls’ Generation. Along with the sub-units of Girls' Generation, she is also a part of other SM’s groups like GOT the Beat and SM the Ballad.
Hyoyeon
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SM Entertainment’s GOT the Beat's female supergroup includes Hyoyeon, another vocalist from Girls' Generation. She was also used to be a part of other SM groups like Younique Unit and Triple T.
Taemin
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Known as “Golden Maknae,” Taemin is the youngest member of SHINee. He is also a member of SM’s supergroup SuperM. Taemin used to be a part of the Younique Unit and SM The Performance too.
Baekhyun
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Baekhyun is the main vocalist of EXO. He is a member of SM Entertainment's Supergroup SuperM in addition to EXO's sub-units.
Kai
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The main dancer of EXO, Kai, also belongs to the supergroup SuperM. He used to be a member of SM The Performance and now disbanded SM group Younique Unit.
Seulgi
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Kang Seulgi is a dancer and vocalist of SM’s girl group Red Velvet and its sub-unit “Irene & Seulgi.” She is also a member of the female supergroup GOT the Beat. She was also one of the members of Girls Next Door and Station Young.
Wendy
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Wendy is a member and vocalist of SM Entertainment’s girl group Red Velvet. She is also a part of the recently formed SM Entertainment’s female super group GOT the Beat.
Hwasa
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Mamamoo’s rapper and maknae Hwasa is also a part of Refund Sisters. Which is a seasonal K-Pop Supergroup formed by the MBC variety show “Hangout with Yoo.”
SinB
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The former member of GFriend SinB is now a member of Viviz. She is also a part of Station Young, another project group formed by SM Entertainment.
Soyeon
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Leader and main rapper of (G)I-DLE Soyeon is a member of Station Young and K/DA as well. Station Young is a project group of SM Entertainment, and K/DA is a virtual K-Pop girl group.
Miyeon
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Miyeon is the main vocalist of (G)I-DLE, who, along with bandmate Soyeon, is a part of the virtual K-Pop group K/DA where she voiced for Ahri.
Seola
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South Korean singer Seola is a member of Starship Entertainment’s girl group WJSN and WJMK, which is a special project unit group between WJSN and Weki Meki.
Luda
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Along with bandmate Seola, Luda from WJSN is also a part of the four-member special project unit group of Starship and Fantagio Music 'WJMK.'
Yoojung
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Yoojung is the main rapper and face of group Weki Meki and is a part of Starship X Fantagio’s special project unit group WJMK along with bandmate Doyeon.
Doyeon
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Vocalist of the record label Fantagio’s girl group Weki Meki, Doyeon, is also a member of the project unit group WJMK along with bandmate Yoojung and two WJSN members.
'Idols who are part of more than one group':
Every SM artist.
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