Two years before the main story.

 

An incident occurred where a large quantity of the Certified Singular Disaster Noise appeared during one of ZweiWing’s public performances.

 

It was a horrible tragedy where in that place, the number of the missing persons, and dead, rose to over 12,874 people, out of the over 100,000 people who happened to be there including the staff, and audience.

 

(Provided that over 1/3 of the entire body of the deceased were caused by Noise, then the remaining were the result of bodily injuries sustained by the acts of violence caused by the people at the top who were competing to ensure their escape route, or people who were crushed to death because they fell on top of one another mid-flight.)

 

This also included Kanade Amou, one of the ZweiWings who were among the deceased, and with this as its trigger, ZweiWing became dissolved.

 

Even now, it is an event that still leaves scars in many people’s hearts.