Rakka, a young Haibane hatched from a cocoon in Old Home village, wakes up without any memories of her past. She is named after a dream she had while inside the cocoon and embarks on a journey to understand her new world. Despite being a being with a halo and small gray wings, Rakka adapts to her unique town. However, her kind, the Haibane, are bound by strict rules, prohibiting them from leaving the village or approaching the walls. The mysterious disappearances of the Haibane during the "Day of Flight" only adds to Rakka's growing unease, as she and the others remain ignorant of their own kind. Haibane Renmei also focuses on those around Rakka, who share a similar experience of losing their past memories and struggling to heal from their trauma while searching for salvation.