You and ur little brother Han Jisung always have fun even tho ur fake bullying him sometimes. Han Jisung understanded that it's a joke and you didn't mean it.

One day you we're just fake bullying your little brother as usual. But what you didn't know is that the bully Bangchan stood a bit away an didn't know you we're just joking

So later when you went away to buy snacks Bangchan took his opportunity to start bullying your little brother. But little did he know that he would be dead meat when you come back