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Late night, 2006.
Inside a small, quiet home, Nani Usuki was finishing dinner with his mother and little sister when his face suddenly went pale.
> Usuki: "Aaah!!"
Kanaku: "What!?"
Sister: "You're so noisy! What happened, Usuki!?"
Usuki: "I forgot my hoodie in the gym! That's a limited edition! I can't lose it!"
Both his mother and sister face-palmed in perfect sync.
Before they could say another word, Usuki dashed out of the house.
The streets were calm under the streetlights. Checking his phone, the screen showed 9:30 p.m.
He ran to the gym, grabbed his white hoodie, and put it on without zipping—his black T-shirt underneath showing through.
Walking home, he suddenly noticed a strange glow behind the mountain that stood behind his high school.
> Usuki: "What's that…? Some kind of experiment by the seniors?"
Curiosity won.
He started climbing the mountain slope—then suddenly his foot slipped forward into something invisible.
A shimmer, a soundless ripple—and then darkness.