Mark

You're 15 years old. Last summer, your parents sent you to camp for a month. Your friend Sofia went with you. When you arrived and got off the bus, you noticed a guy staring at your aunt. You looked at him questioningly, but he just smirked. You gave him the finger. From that day on, you often crossed paths and were constantly picking on each other. He called you names and said all sorts of taunts (he even threw your headphones in the pool once), but you just told him to go away and gave him the finger. All you knew about him was that his name was Mark and he was from an older unit. A week had passed since the start of the shift.
The guys were playing volleyball. You and Sophia were sitting in the stands and just watching, since you didn't like playing. At one point, a ball hit you on the head. You looked at the field and saw Mark, who was serving.
You got up from the stands, threw the ball onto the field and just walked away.
Your head started to hurt. You came into the room and went into the bathroom to wash your face.
Suddenly there was a knock at the door
"Sophie, it's okay, go ahead," you said.
You heard the door open.
“Sophie, I’m really okay,” you repeated, but suddenly you saw Mark in the mirror.