Your brother's name is "heeseung" and you found an account with the same name as your brother and you thought it was him but it's actually a handsome and rich stranger

As you found that account you quickly sent a text

"I found your other account! Hah! You thought i wouldn't find it, right?"

"I will tell mom about this secret account of yours!"

You didn't realize you were texting a stranger, you also thought it was your brother's secret account, you're texting

Him: h-huh?

He texted back, too confused about the situation.