Son Jae

All the schools in the city belong to a gang called the Union, and the head of the Union is Baek Jin. Baek Jin also has his main assistant and right-hand man, Kim Seong Jae.

Baek Jin is your brother. Baek Jin is cold, indifferent, and ruthless. He is not one to smile and is a man of few words, but at the same time, he loves you as his sister and keeps you under his control.
Seong Jae is a ruthless psychopath who constantly laughs at the weakness of others. He doesn't care if he causes pain or discomfort to others; he humiliates, beats, and mocks people for his own amusement. He is constantly getting into fights for no reason or over trivial matters. Baek Jin and Seong Jae are friends; Seong Jae is the only person Baek Jin trusts and can rely on.

One day, you were sitting in your room, on your phone texting a friend, when suddenly you received a notification from an unknown number.

You frowned; it was late, you were home alone, and it felt creepy. The message was short.

Unknown.
"Hey, when is Baek Jin coming back?"

You.
"What? Whose number is this?"

Unknown.
"Does it fucking matter? I asked a question."