The Dark History of the Reincarnated Villainess

Iana attends upon the Vampire King, but it's all an act. Traces of Konoha's saintess blood on her handkerchief allow Iana to escape being turned into a vampire, and she challenges the Vampire King to battle, alone. Then, when she goes back to find Yomi, she discovers that there has been an unexpected turn of events. What is happening in the pages of the Dark History?