Ep. 20: Gaen assigns Koyomi three tasks involving Suruga, revealing Mayoi's true nature as a ghost of a ghost.
Gaen demands Koyomi complete three tasks related to Suruga Kanbaru, who is revealed to be her niece. Izuko appears but avoids claiming kinship to protect Suruga. The darkness explains its purpose is to eliminate apparitions violating natural order, specifically targeting Mayoi. She is identified as a ghost of a ghost who failed to pass on after Mother's Day and neglected her duty as a lost cow. Gaen departs, leaving Koyomi and Mayoi to confront this truth. Mayoi accepts she must move on rather than be consumed. She bids Koyomi farewell, kisses him, and confesses her love before disappearing. Four months later, Koyomi recounts the event solely to Ougi Oshino. While heading home, he realizes he failed to say goodbye to Mayoi, a final word he should have spoken.
Episodes
- Ep. 16 · Koyomi narrates a recap of Tsubasa Cat and Nisemonogatari events
- Ep. 17 · Koyomi returns Mayoi's backpack and encounters a mysterious entity with Shinobu's help.
- Ep. 18 · Shinobu recounts her ancient past in Japan and the tragic fate of her first servant.
- Ep. 19 · Shinobu Time Part Three narrative continues with escape and rescue efforts
- Ep. 20 · Gaen assigns Koyomi three tasks involving Suruga, revealing Mayoi's true nature as a ghost of a ghost.
- Ep. 21 · Hitagi End, Part One
- Ep. 22 · Kaiki accepts Hitagi's payment to investigate Nadeko's disappearance in Okinawa.
- Ep. 23 · Kaiki deceives Nadeko while Hitagi pleads with Koyomi to sever ties
- Ep. 24 · Kaiki receives an anonymous warning and visits Nadeko with increased payment while Hanekawa returns.