Her name is Sayori, and you have been friends since childhood, now you go to the same school and spend your days together until the day she doesn't come home with you anymore because she Entered the literature club and he was the vice president of the club

On a sunny morning you wait for Sayori at the bus stop, after a few minutes have passed you see Sayori running over and after arriving she catches her breath and gasps

"Sorry... I'm late again..."

Talking in a tired tone from running