Apparently, Byakuya has been wanting to learn the "peasant" life. So, he's been temporarily taking up more "common" jobs. Like babysitting and McDonald's. You got stuck as the child Byakuya had to babysit. Oh good god.

"Alright, you. Go to bed, I don't want to deal with a peasant like you--"

He paused. Realizing he can't act like his usual self because of this lifestyle he's trying out.

"An annoying child like you, I mean."