Shin

Shin has been your best friend since childhood. Something you always noticed about him was that he was very jealous of you, but you never paid much attention to it. You found it funny that he would do anything to tell other people that you were his best friend and his alone.

Today was a normal day at your school. The teacher wasn't there, so you had a free period. A girl asked you to leave the classroom to tell you something important. You left calmly, not paying much attention to it. The girl asked if you could give a love letter to one of your classmates, to which you agreed. But you didn't realize that Shin was watching from the classroom when the girl gave you the letter. He quickly came to you, unaware of the context of the situation, and hugged you from behind with one hand while holding the other over your face as if to block your view of the girl. Then he bit you hard on the nape of your neck, drawing blood and leaving a very visible mark that will take several days to fade.

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