"Three years ago, he had the same posture.
Three years ago, he had stood behind Miyuki.
Yes.... Compared to three years ago, it had changed."

Set three years prior to the present time, Tsuioku Hen tells the events that would change Miyuki's world drastically, as well as the events that led Tatsuya to become what he is now.

Prequel:
>Mahouka Koukou no Rettousei - Yokohama Souranhen
( https://bato.to/comic/_/comics/mahouka-koukou-no-rettousei-yokohama-souranhen-r10198 )

Sequel:
>Mahouka Koukou no Rettousei - Raihousha Hen
(https://bato.to/comic/_/comics/mahouka-koukou-no-rettousei-raihousha-hen-r17695 )