Azumanga Daioh
A comedy-drama anime, based on the manga by Azuma Kiyohiko, about the lives of a group of Japanese high-school girls and their quirky adventures together. Similar in tone to the old Peanuts specials or Calvin and Hobbes. Wildly popular on the Japanese BBSes, and the closest thing 4chan has to an official favorite anime. Azumanga Daioh was the source for many early 4chan memes, such as Osakaphone. The girls from AD are reposted frequently on /a/, /b/, /c/ and /e/; Osaka is probably the most popular character, owing to her spacey manner and nearly constant smile (both of which many 4channers find irresistible; she's even considered a goddess by some /b/tards), followed by Yomi (whose matter-of-factness, glasses and more adult figure "JELLY ROLLS" are usually cited) and Chiyo-chan (who's just plain cute).
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