Karasuma Kumiko wa Miko de Nai

Hero History Apocrypha (勇者史外典) part 3 of 3. It's the summer of 2015, 300 years before the time of the TV anime "Yuuki Yuuna wa Yuusha de Aru", and "that day" when humanity was destroyed. One of the first Heroes, Takashima Yuuna, has been shrouded in mystery until now, except for the fact that she is