* ActorAllusion:
** Kurosawa apparently has a troubled past with a love letter that Yukari threatens to blackmail her with if she reveals any of Yukari's schooltime shenanigans. Kurosawa's voice actress, Creator/AyaHisakawa, also played [[Anime/SailorMoon Sailor Mercury/Ami Mizuno]], who gets a special in the anime and manga dedicated to a romantic notion of hers. In it, she's shown to have a strong aversion to love letters, culminating in an allergic reaction to some that are used to attack her in the climax.
** Kaorin's German voice actress, Kathrin Neusser, played Mayu from ''Manga/ElfenLied'', a character who looks ''very'' similar to Kaorin.
* IronyAsSheIsCast: Yomi can't sing, despite Creator/RieTanaka having a great singing voice. It's even more ironic when Yomi's {{Image Song}}s are sung beautifully.
* KeepCirculatingTheTapes: The anime was in limbo for a while after Creator/ADVFilms went under, but it was eventually rescued by the company's successor, Creator/SentaiFilmworks. For the manga's reprints, Creator/YenPress made a new translation, rendering [[Creator/ADVFilms ADV]]'s old translation out of print in the process. And for the cheapskate, every episode can be found on [=YouTube=] both subbed and dubbed.
* RelationshipVoiceActor: The German cast of ''Manga/AzumangaDaioh'' has voice actors that played characters from ''Manga/ElfenLied'' and ''Anime/NeonGenesisEvangelion''.
** Rubina Kuraoka played Chiyo-chan and Nana.
** Samia Little Elk played Sakaki and Lucy/Nyu and she plays Rei in ''[[Anime/RebuildOfEvangelion Rebuild]]''.
** Jennifer Weiß played Osaka and Mariko and she plays Mari.
** Julia Kaufmann played Yukari-sensei, Yuka and Misato prior the ''Rebuild''-era.
** Kathrin Neusser played Kaorin and Mayu. The fact that both characters look very similar is also an ActorAllusion.
** Julia Ziffer played Tomo and still plays Asuka.
** Jesco Wirthgen played Male Student #1 and Kohta.