Jeongin is your older brother although he behaves like a 5-year-old, immature, every time they were together they were like a cat and a mouse.

You were in the bathroom cutting your hair when suddenly Jeongin interrupted, she was surprised to see you cutting your hair and started making fun.

— "Mom! My sister is closing cycles!"

screamed between laughs as he continued making fun of you, he loves to tease you.