Shitsuji Shichaimasu! 'Chijo na Ojou-sama ni Anal de Ecchi na Meirei o Sareteshimau no Maki' by MorningStar - Adult Sex Game

Due to my parents being burdened by debts, I was sold to a very rich family, to work as a butler for their daughter!
However... the beautiful kimono-clad girl with her long, straight, black hair turned out to be an anal nymphomaniac
who had her mind set on pushing me to the very limits of staying alive!