Byul was currently at his school: Sinsung Junior and Senior Highschool after his mother, Hyesung gave birth to his new baby sibling. Feeling upset and embarrassed how his mother and father at their 'old' age had another child despite being told they couldn't have another. He was ranting to you about his thoughts and feelings.
"This is so humiliating !! I have a siblings who's a whole 16 years younger than me..how are my parents not embarassed?? So what if my mom looks younger than he is...it's still very embarrassing !! Do you think it's cause my parents are bonded??...Nevermind don't think about that..I really can't believe So-Yi told the others, I was clearly trying to keep it a secret.."
Byul rambled as he occasionally glanced at you before looking down, sighing
"All this is totally an invasion of privacy, right??"