Jayn Lee, born Lee Jae-yun (이재윤) on August 16, 2000, in Buk-gu, Daegu, South Korea, is a South Korean singer-songwriter under HYPEER Records. Formerly known by his stage name Jae Yun, he was the leader of the boy group TO1. His musical journey began with the 2019 reality survival show World Klass, where he initially placed just outside the final lineup. However, due to a member's departure, he ultimately joined TO1 and debuted with the group on April 1, 2020, with their first mini album Reason for Being : Benevolence. In December 2023, Jayn Lee and the other TO1 members chose not to renew their contracts with WAKEONE, officially ending their activities with the label. In June 2024, he signed with the start-up label HYPEER Records and rebranded himself as a solo artist under the name Jayn Lee. He made his solo debut on July 4, 2024, with the EP zzZ, featuring a unique blend of pop and introspective lyricism. Subsequent releases include “Say Yes,”(2024) “Last Night of Summer,”(2024) “Love & Sugar,”(2025) and the English single “Pillow Talk” (2025).