The Y U No meme features a crudely drawn character with a look of extreme frustration and wide-open eyes. It originated from the Japanese sci-fi manga series Gantz, specifically from a facial expression made by the character Kei Kurono in Chapter 55. The drawing was later modified and popularized on 4chan and Reddit around 2010. Known for its signature 'Y U NO [Action]' text format, the meme uses simplified grammar to demand an explanation for something the speaker finds annoying or illogical. It remains one of the most foundational templates of the early rage comic era.