It's a picture of Sakamoto Ryouma, who was the husband of Narasaki Ryou,
i.e. the person who Oryou bases her persona on
An ever-lasting battle-field
For the members who live in the History Girls' house .....As always, we have been given the right to ambush each other!Prepare yourself ze yo, Saemo-nza!!What's this
~~!?You've put a picture of him on your back!?I can't...
I can't hit you like this ze yo...!You're wide open〜