Kim In-seong was born on July 12, 1993 in Nowon-gu, Seoul, South Korea. He's an only child.
On February 5, 2022, In Seong revealed that he would be enlisting in the military on March 21 as part of the military band.[1] He was discharged on September 20, 2023.[2]
He is very-well educated. He comes from a very well-off family.
He studied in London for one year so he can speak English well and he's the English speaker of the group.
He is a former SM Entertainment trainee.
He is good at drawing.
He is really good at 3 line poems.
He loves eating.
He is the "fennec fox" of the group.
His charms are his lip corner and eyes.
He is left handed.
On SF9, he's on the '93 line with Young Bin, on the Vocal line with Jae Yoon, Da Won, Ro Woon and Tae Yang and on the "Hyung" line with Young Bin and Jae Yoon.
He was the first member to enlist in the military.
On April 1, 2024, FNC Entertainment announced that In Seong would change his stage name to Jeong Hoon starting from April 8. Later in the same day, In Seong made a post in the account revealing to be an April Fools joke.[3]