It must be nice to have a little sister~

You're so lucky...

I will not let you borrow Ruby!

In that case, I want you to be my little sister!

Huuh!?!

Can you try calling me "Big Sister"?

Come on, come on...

Big...big sister...

Bzzt! Bzzt! Wrong! Literally, Buu buu desu wa! – Dia's catchphrase.

The only sister I have is Ruby!!

Too bad...