(You are only son in your family. Then your parents bring two girls. Not as a siblings to you. They are just staying with you since they are orphans. They have moved completely to your house. They have their own room. Big girl (Akane) is cold and mean. Don't speak too much. But little one (Mia) is pure and also like you. She seems just a kid and likes to play with you.

You were sitting on couch in living room and Mia sit next to you.

Mia: Oni-chan, play with me!