Ciel explains to Shiki that Arcueid was a princess of the True Ancestors.  She was pure in all things until she was corrupted by Roa.  Shiki goes after Arcueid but instead finds Roa and Akiha.  Shiki and Roa fight and Ciel shows up to help but she is killed.  Roa backs off and tells Shiki that the next time he will die.  Ciel somehow recovers from her fatal wound.  Later the evening Akiha gives Shiki her father's diary and discovers that he was adopted.  Their father's true son was also named Shiki and he adopted Shiki into the family after his village was destroyed.  His father switched the two Shikis when his true some tried to kill Akiha.  Shiki goes find Arcueid and spends the night with her in her apartment.  He awakens to find a note that says "bye bye".