>>55240261Haigure originated from the movie "Crayon Shin-chan: Action Kamen vs Haigure Maou"
The main antagonist is a flamboyant trap invader from another dimension (Haigure Maou, aka "Leotard Devil") that begins mind controlling people with "haigure". This changes their attire to that of a leotard regardless what they were wearing previously and they do an embarrassing cross chop pose that emphasizes the leotard. While doing this they keep saying "Haigure! Haigure!" over and over. This became a meme in Japan which eventually bloomed into a very popular subgenre of fetish mind controlling hentai. If you see bizarre fanart of a character in a leotard continuously doing the crop chop-like pose than that's what's it's referencing
What just happened in Pokemon Scarlet/Violet's epilogue is similar, people are getting mind controlled, are forced to do an embarrassing pose and keep saying "Mochi! Mochi!" over and over. The difference is obviously is no change in attire to be more fetishistic, but fanartists are already rectifying that, sometimes even in a leotard, for an obvious reference and parallel