The Irregular at Magic High School, Vol. 8 (light novel)

In 2092, Okinawa was suddenly invaded without warning by an unknown enemy force. Miyuki and her mother were caught up in the battle that ensued, leaving them in dire straits where they were all but helpless, relying on the help of a lone young man...named Tatsuya. This is the story of how the Shiba siblings got where they are now!