My Wife From a Parallel Universe

On the last day of April, second year high school student Yamamoto Sayaka of class 2-1 disappeared.

No newspaper reported it, and no police report was filed. None of her friends and family seemed to notice that she was missing; it was as if she hadn't disappeared at all.

But I was sure that Sayaka was missing, because I was the only one who noticed that she was gone.

[Present-Day - Chance Encounter]