While carrying the unconscious Reg back home, Nanachi remembers when several children, including Mitty and them, were taken in by the White Whistle Bondrewd to his base deep in the Abyss, unaware that they were to be used for his experiments. In one of them, Nanachi and Mitty were sent together to the sixth layer and afflicted by the Curse of the Abyss upon being taken back, leading to their current appearances. After Mitty, who was turned into an immortal creature, was unsuccessfully killed several times by Bondrewd, Nanachi decided to flee with her. After considering Nanachi's request, Reg decides to accept it, and Nanachi bids farewell to Mitty before Reg destroys her completely with the Incinerator. Some time later, Riko awakens, but has lost most of her left hand's movements. Riko and Reg then asks Nanachi to join their quest to meet Lyza, and they agree. After sending a message to the surface that is received by Shiggy and Nat, Riko, Reg and Nanachi make their preparations before leaving to the fifth layer. At the same place Nanachi fled from, Bondrewd discovers that Mitty's life signature disappeared, realizing that Nanachi managed to somehow kill her, and is eager to meet Nanachi again.