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Reisen Udongein Inaba's alternate palettes are references to the characters of the popular "Vocaloid" programs.

Her palettes resemble, in order, Miku Hatsune, Rin Kagamine, Luka Megurine, Meiko, Kaito, Gakupo Kamui and Gumi.
Contributed by TailsFiraga
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The character Utsuho Reiuji has several sprites and animations that bear resemblance to the character Thouzer/Souther from Fist of the North Star. This includes one of her Spell Cards in the game, which bears a resemblance to Souther's Fatal K.O., "Nanto Hō-ōh Ken Ougi: Tenshou Juuji Hou."
Contributed by TailsFiraga