Several stories told to her in the hospital by the seaside

So Uehara visits the hospital by the seaside.

Once he lay here with friends, but most of them died during an outbreak of an unknown disease.

Those who were fortunate enough to survive are still undergoing treatment.
So recalls and tells about what happened on that very day: about how an epidemic broke out in a provincial town, claiming all the adults and granting superpowers to the children, and what the outcome of the battle was...