In 2017, Hongseok appeared in the film "The love that's left"
According to Jinho, Hongseok is the best at cooking in Pentagon.
He loves reading books and studying languages.
When Hongseok was a child, his family kept moving from San Diego, Singapore, and China. Because of this he's able to speak English, Korean, and Chinese.
Hongseok loves Iron Man.
Hongseok and E'Dawn are roommates back in Pentagon's dorm.
Aside from YG Entertainment, Hongseok also tried to audition for JYP entertainment but was eliminated.
Hongseok used to be a YG Entertainment trainee and was a contestant of MIX&MATCH (the show that made iKON).
Hongseok thinks his best attribute is his abs.