It's possible! Is this character someone in the game? An NPC? I would need to know more about him and his role (and preferably talk to the player) in the game to really make that determination.

I could see her giving Touya a hard time about picking on Xiaolang at the very least, if she sees it is a regular thing. It's okay, Xiaolang, it's an older sibling thing! He's (probably) harmless.