Ep. 12: Nadeko Medusa, Bagian Satu

Fully transformed into an apparition, Nadeko confronts Shinobu and a battered Koyomi who attack with the intention of killing her, and envious of their relationship, she stabs Koyomi's heart. The story then retrocedes to some days before, in Halloween, when Nadeko, on her way to school has a short encounter with Ougi Oshino, Meme Oshino's niece, who is also a first year student Koyomi's high school. For some reason, Ougi claims that it is about time for Nadeko to stop always playing the victim before she leaves. At her school, Nadeko starts having visions of white snakes and calls Koyomi for advice, and they agree to meet at 10 PM at his house, as by that time Shinobu must be awake to provide some help. Soon after, Nadeko hears the voice of a snake instructing her to meet it at the shrine where she used to kill snakes instead and there it reveals itself as the giant apparition snake, Kuchinawa, who demands compensation for its fellow white snakes she killed by asking for a favor, to which she agrees. (Source: Wikipedia)
Episode
- Ep. 8 · Koyomi mencoba menyelamatkan Mayoi dari takdirnya namun mengubah sejarah yang berujung pada kehancuran global
- Ep. 9 · Koyomi dan Shinobu menghadapi kota kosong akibat menyelamatkan Mayoi
- Ep. 10 · Koyomi dan Mayoi berjalan pulang setelah menyelesaikan krisis garis waktu alternatif.
- Ep. 11 · Koyomi merangkum kembali peristiwa Bakemonogatari dari Hitagi Crab hingga Nadeko Snake
- Ep. 12 · Nadeko Medusa, Bagian Satu
- Ep. 13 · Nadeko Medusa Bagian Dua narasi berlanjut dengan Nadeko dan Kuchinawa mencari jasadnya
- Ep. 14 · Nadeko Medusa, Bagian Tiga
- Ep. 15 · Nadeko Medusa Part Four menguraikan dampak setelah Nadeko menelan jimat dan mengalahkan Koyomi serta Shinobu.
- Ep. 16 · Koyomi merangkum kembali peristiwa Tsubasa Cat dan Nisemonogatari