- The ending theme, while pretty, is quietly unsettling, especially at the end when Rakka dissolves into feathers.
- Rakka growing her wings.
- The bird skeleton in the well.
- The walls, as not only does touching them bring you close to death, they project what you want to hear from them so you're compelled to touch it.
- The Railroad Tracks of Doom in Reki's room near the end of the series.
- Reki not being found until after her wings erupted. Has a new Haibane ever died from lack of care?
Nightmare Fuel / Haibane Renmei