Kim Se Jung said, "I'm in the unnie line (older members) of IOI. The dongsaengs (younger ones) do aegyo to me and take care of me. In Gugudan, I'm in the dongsaeng line. The unnies take care of me well. I can lean on my members, so it isn't hard."
She also revealed that in order to become a singer, she went around with a list of 20 companies. She said, "I wasn't sure which company I'd get into, so I decided that I couldn't just focus on one - I had to have backups. I wrote what the auditions were like for each company and what they focused on, then prepared accordingly."