About

Waha~ (No, not the amateur hockey league) is a cute anime girl (see Moe ) that was widely prevalent on 2chan and 4chan's /b/ and /jp/ boards.
Encyclopedia Dramatica depicts her as an "Old Meme" .

Origin

While becoming popular on 2chan, and then crossing over to 4chan, Waha~ is a fanart image of a character named 'Suzuran' from a hentai game called 'Suigetsu'. The reason she is called 'Waha~' is because she yelled it out after every one of her lines in the game. (source)

Youtube Fad

SuperWaha~ is a placement of videos using a higher pitched version of the song SuperGirl by Papaya. It was later made into a game.
The earliest video was posted on May 27, 2007. While the view counts are low, it is still somewhat notable.