They need to complete the missions to survive. But in order to complete the missions, they must sacrifice their close one – their own classmates.

            *(This fanfict is inspired and based on EXO – Angel’s lyrics)               A person whom I found accidentally in the forest when I got lost, a person who walked side by side with me, a person who wiped away my tears on my hard days, a person who always stayed by my side and a person who always protected me.             But even though we got closed, his identity and origin is still a secret.