Satsuki Arashiyama

Satsuki Arahiyama is Jinpachi's younger sister who is often seen with a wooden sword. She initially perceives Nanaka as a hussy for making Jinpachi act all weird around her, so she tries to attack Nanaka, but Nanaka unintentionally dodges her attacks easily. After Nanaka "saves" her from a falling shard, she begs for her forgiveness and wants to be her disciple and she can address Nanaka as Oneesama (big sister). She then "trains" Jinpachi harder so he can be a worthy suitor for Nanaka. Her attack catchphrase is "You're wide open!"