I.O.I has made a successful comeback after 9 years, with their title track '갑자기' topping music charts. Members 소혜 and 나영 will be participating in a baseball game as pitch hitters. The group's reunion activities have been well-received by fans and the general public, with their music topping charts such as Melon's TOP100 and HOT100. | I.O.I has made a successful comeback after 9 years, with their title track '갑자기' topping music charts. Members 소혜 and 나영 will be participating in a baseball game as pitch hitters. The group's reunion activities have been well-received by fans and the general public, with their music topping charts such as Melon's TOP100 and HOT100.