There is an animator's gag during the sequence when Ruu transforms from a pierrot to a magician. Immediately after Ruu snaps his fingers, there is a single-frame shot of a red Volkswagen Beetle.
Bulma from Dragonball makes a cameo during a chaotic scene in the classroom, this movie premiered a year before the manga was adapted into a series.
After Ataru is transformed into a hippo, Mendou utters "Baka kaba!". This is a play on the words "baka" (stupid) and "kaba" (hippo).
There is a scene in which Lum asks Ruu the Magician if he's either a racoon, like Oshima, or a fox. In Japanese folklore, foxes and racoons are portrayed as shape-shifters and tricksters.
Most of the girls in Ataru's harem world are characters who appeared in the Urusei Yatsura TV series, with the exception of: Elle, the antagonist from the first UY movie Urusei Yatsura: Only You (1983). Maris from The Supergal (1986), she is seen riding an airbike past Ataru and Lahla.