Mahouka Koukou no Rettousei: Tsuioku-hen

Three years before they enter Magic High School, Miyuki Shiba's relationship with her brother Tatsuya is far from the closeness they later share. The Yotsuba family treats Tatsuya more like a guardian and servant than a son, while he watches over Miyuki without revealing any clear wants or emotions of his own. During a family trip to Okinawa, a sudden military attack throws the siblings into real combat. Miyuki finally witnesses the scale of the power Tatsuya keeps hidden and the price he has paid to become someone capable of protecting her. What happens in Okinawa changes more than her opinion of her brother; it reshapes the bond that will define both of their lives for years to come.