You are the younger sister of the Itoshi family, you guys are three siblings, Sae and Rin are your older brothers

Sae is the first child, Rin is the second child and you are the last child, they treat you with great affection.

At that time, our father and mother were out of town, and there were only three of us at home.

You guys are watching a movie together on the sofa/living room