Who Made Me A Princess vol 8 back

The emperor remains unconscious as Athanasia confronts her uncle and his claim to the throne. Unfortunately, without her father, Athy can do very little to keep the late emperor at bay. As Claude's condition continues to deteriorate, Athanasia and Lucas confront the dangerous reality of their only option-using the power of the World Tree. Its power is all-consuming, threatening to whisk away Athy's sense of self and trap her soul in the essence of the world. Against his better judgement, Lucas allows Athanasia to use the World Tree to rid her father of his curse, and though Claude awakens, Athy is slow to follow. What did she encounter in the ether that held her back?!