It's the year 2020. It's a calm day as our protagonist sits atop the roof of his school building watching the sky As the sun sets, he turns around. Only to see a mysterious girl standing at the edge of the building outside of the protective railing. She's about to jump. He runs her way in an attempt to stop her. About two armlengths away she threw herself forward. Our protagonist took the most impulsive decision he had ever made... He jumped after her.
3 parts