Mortimer Mouse's 'Ha Cha Cha' originates from the character's long-standing role as Mickey Mouse’s arrogant and sleazy rival, most notably popularized in the Mickey Mouse Works and House of Mouse animated series. The phrase is accompanied by a distinctive, swaggering dance that perfectly encapsulates Mortimer's overconfident and annoying personality. In internet culture, the meme took off as a way to represent someone 'stealing your girl' or acting with unearned confidence in a cringeworthy yet hilarious manner. It often appears in video edits and image macros to signal a sudden, unwanted, but flamboyant intrusion into a situation, making it a favorite for those who love high-energy, classic cartoon trolling.