On September 18th, FNC Entertainment, the agency of SF9, officially announced Rowoon's departure through the group's fan cafe.
FNC stated, "SF9, who has been active as artists under our label for seven years since their debut in 2016, ended their first contract on September 18th. SF9, except for Rowoon, who had already renewed his contract with the company, will once again leap forward as an eight-member group."
Following this, Rowoon posted a handwritten letter to convey his feelings about leaving the group and to apologize to his fans.
Rowoon stated, "There were times when I needed the courage to confront misunderstandings, but I always chose to hide. If there are fans who have been hurt and disappointed by my careless attitude, I'm truly sorry. If you felt a sense of unfamiliarity in my changed self, that's also because I ended up hiding."
He continued, "I want to try new challenges as I turn 27 this year. I was unsure how to express this, but I want to say I have the courage to take on new challenges. Please watch over me so Kim Seok Woo, at 27, can live a life for which he can take responsibility. I will remain the same as you remember."
SF9 debuted in October 2016, and Rowoon has been actively involved in acting and working with SF9 since 2017. Currently, he is appearing in the JTBC drama Destined with You.