Nani comes from the Japanese word for what and has been a staple expression of shock in anime for decades. Online, exaggerated versions of the shout were clipped and shared as standalone reactions on meme pages, video edits and soundboards. Its appeal is how clear the emotion is without subtitles, making it easy to reuse across different scenes and jokes. It is now often grouped with other anime staples like the To be Continued JoJo ending for comedic edits and reaction compilations.