The phrase comes from Shinryaku! Ika Musume, known in English as Squid Girl, where the squid heroine Ika Musume ends many of her sentences with de geso as a playful verbal tic. The anime adaptation helped the line travel beyond Japan through clips, fan edits and soundboards, where short catchphrases are easy to reuse. It remains popular because it is instantly cute, distinctive and only a fraction of a second long, making it perfect for quick reactions and anime-themed jokes.