* The mangaka is a huge fan of ''ThePowerpuffGirls''
* According to the mangaka, she was approached about turning Ultra Maniac into an anime ''before it was ever published.'' Which explains why the anime and the manga have so little in common.
* [[HeyItsThatVoice Hey, It's That Voice!]] -- Hilariously, Ayu and Nina are ''DaCapo'' [[RelationshipVoiceActor co-stars]]. See below!
** [[Creator/YuiHorie Ayu Tateishi]] is SchoolIdol Kotori Shirakawa dumping singing for tennis and is still quite the shy girl.
** [[Creator/AkemiKanda Nina Sakura]] is just as [[GenkiGirl energetic]] as Miharu Amakase with one catch: more [[MagicalGirl magical]], less [[RobotGirl robotic]].
** Kaji Tetsushi is Creator/HiroshiKamiya, when he's playing the [[NiceGuy nicer characters]].
** In the english dub, Pine from episode 8 has the same voice as [[Anime/ALittleSnowFairySugar Sugar]].
** In Japanese and English, Ayu Tateishi is [[Anime/MarsDaybreak Megumi Higashihara]].
** Nina's grandfather is [[VideoGame/SilentHillShatteredMemories Dr. Kaufmann]].
* RelationshipVoiceActor -- Nina Sakura and Ayu Tateishi voice actresses are present and accounted for in ''DaCapo'', which runs just two months after ''Ultra Maniac''. The two reunite as Asuna Kagurazaka and Makie Sasaki respectively in ''MahouSenseiNegima'''s AnimatedAdaptation a couple of years later.