I.O.I (Lim Na-young, Chungha, Kim Se-jeong, Jung Chae-yeon, Kim So-hye, Yu Yeon-jung, Choi Yoo-jung, Kim Do-yeon, and Jeon So-mi) has successfully reunited for their 10th anniversary, marking their return after a 9-year hiatus. The group released their third mini-album, 'I.O.I : LOOP', on the 19th, with the title track '갑자기' reaching number 1 on the Melon Top 100 chart. On the 29th, the group kicked off their '2026 I.O.I Concert Tour: LOOP' at the Jamsil Indoor Gymnasium in Seoul, performing for 4,000 fans and confirming their enduring popularity and teamwork. - I.O.I achieved a number 1 ranking on the Melon Top 100 chart with their new comeback single '갑자기'. - The group launched their '2026 I.O.I Concert Tour: LOOP' on the 29th at the Jamsil Indoor Gymnasium, signaling the start of their Asian tour. | I.O.I (Lim Na-young, Chungha, Kim Se-jeong, Jung Chae-yeon, Kim So-hye, Yu Yeon-jung, Choi Yoo-jung, Kim Do-yeon, and Jeon So-mi) has successfully reunited for their 10th anniversary, marking their return after a 9-year hiatus. The group released their third mini-album, 'I.O.I : LOOP', on the 19th, with the title track '갑자기' reaching number 1 on the Melon Top 100 chart. On the 29th, the group kicked off their '2026 I.O.I Concert Tour: LOOP' at the Jamsil Indoor Gymnasium in Seoul, performing for 4,000 fans and confirming their enduring popularity and teamwork. - I.O.I achieved a number 1 ranking on the Melon Top 100 chart with their new comeback single '갑자기'. - The group launched their '2026 I.O.I Concert Tour: LOOP' on the 29th at the Jamsil Indoor Gymnasium, signaling the start of their Asian tour.