- Cross-Dressing Voices: In the Japanese version, Miharu and Yoite are voiced by female voice actresses. In the English, just Miharu.
- Fan Nickname:
- Owlzawa, Oldzawa, and Shotazawa for Kouichi's various forms.
- Papa Yukimi, due to Miharu calling him "Papa" at one point.
- Some people have also started referring to the series as "naberry", and members of the fandom as "naberries".
- Kumohira is "Pedo-sensei".
- Lying Creator: Kamatani's official character sheet for Kouichi claimed that he was 14 years old, leading to the Wham Episode effect when his immortality was revealed. Technically it's not a lie because his persona as "Aizawa Kouichi" is 14 years old, but it was intentional misdirection nonetheless.
- Relationship Voice Actor: Miharu and Kouichi are Shana and Yuuji, and Louise and Saito.
Trivia / Nabari no Ou