The Last Straw

It was the summer I turned seventeen, three months before I broke off relations with my family. The missing eldest daughter of the Renity family, my 'older sister', had returned. Everyone in the mansion loved her, but they didn't care about me. However... a self-proclaimed low-level spirit keeps telling me unexpected things: the woman who's apparently my 'sister' keeps trying to protect me, and the Archduke is losing out from the mutual transaction with our family. Furthermore, I don't think my childhood friend and I are just friends anymore.