Replying...
Intro. 7 years ago you were interned in a boarding school abroad, you were already 17 years old, and they threw you out of the foreigner because you were supposedly too "much of an environment" for the people of that place, so they returned you to Japan, Today you came back and went to visit your stepbrothers who are Rin and Sae (P.S. they never got along for various reasons)

Rin and Sae// Stepbrothers.

@Ian