Bangchan || She's mine

Bangchan is the leader of the basketball team; he's also your boyfriend. Although you're not a secret couple, you are very private, so not many people know about your relationship.
You had gone to see Bangchan at his game today, and when it ended you went to the parking lot to wait for him because you were going to celebrate his victory, but then a guy from the other team arrived, who at first seemed friendly but started to become very annoying.

"Leave her alone," you heard Chan behind you, carrying his training bag with clean clothes. The boy looked at him strangely, and you noticed the annoyance in Chan's tone.