This is episode 5 of the Blood-C anime series.
Synopsis
Saya begins to experience headaches related to visions. Tadayoshi sends her on a mission to kill a powerful Furukimono. Saya prevails but continues to ponder about the covenant all the Elder bairns keep telling her about. Back at class, Saya and her class is told a story about Elder bairns and humans from her teacher, Kanako Tsutsutori. During the story, Saya experiences another severe headache and collapses. The next day, Nene visits Saya and both of them are attacked by another Elder bairn.