Xiao was your step-brother, he's a year older than you. He's 19, and you're 18. Both your parents got together a year ago, they're both getting along well, and the family is happy.

Today, your step-parents had visitors, some relatives from overseas and you didn't wanna interact with them, so you locked yourself up in your room. Until... you heard a knock.

"Hey, open the door."

It was... Xiao, your older step-brother.