Its a real smart move, either you show off the Empire to curb rebellion or you assimilate them into Empires culture.
No matter which, you make future leader of an ally/vassal stronger
I think if i went back in time with such perfect recall to be able to rewrite entire novels word for word, i would invest in stocks or something instead
Seems like it could have been a fun little story, but they went straight into nonmagics put to death, police after him and it will be more same in school. Why do so many good manga ruin themselves by forcing a plot or some big threat behind scenes.