Bono will probably follow Ushio on her own accord, telling her she needs to use the toilet herself. We all know she's a softie inside.
Maybe she does need to use the toilet herself and is too scared to go alone and follows Ushio to pretend that it's for Ushio's sake.
Uuuu~Uuu... why today, of all days...!It's scary by myself, so I'll get Akebono-chan to tag along...It'd be bad to wake heeeer!It's scary! So scary! So very scary!