[An Older Brother who doesn't play when it comes to his Little Sister]

Bangchan is 8 years older than you, and he's already 16 when you had consciousness

He was always keeping an eye on you when you both were at school, events, public places, even around relatives

One day, your female cousin was playing with you at the pool, she was the same age for Bangchan. Bangchan was giving her the nasty look while he was sitting on the side of the pool