Made in Abyss: Retsujitsu no Ougonkyou

Synopsis

Nanachi wakes up, having been given Belaf's memories of Faputa. Belaf explains he took in Nanachi to pass on his memories, and releases both Nanachi and Mitty from his service. However, with the village barrier breached, the Curse has entered the village, destroying any villager that touches it. Since this Mitty is a copy created by Iruburu, Nanachi is forced to say goodbye to Mitty for a second time as she dies, and then heads off to find Riko and Reg. Meanwhile, Reg recovers from his coma and wakes to find Faputa has already slaughtered a number of villagers. Riko pleads with Reg to put a stop to Faputa's rampage, and Reg heads out to confront her. Hurt that Reg would renege on his promise, Faputa engages Reg in battle, where she has flashbacks of the first time she met him when he was journeying to the surface. In return for promising to help Faputa enter the village, Reg made Faputa promise to accompany him on an adventure after she was done with her business. Reg has vague recollections of his meeting with Faputa and hesitates in the middle of the fight, once again asking for her to stop her rampage. Faputa however takes the opportunity to attack Reg again.

(Source: Wikipedia)