Wing

Some info and a short description of this South Park episode on South Park Zone:
South Park - Wing is episode 128 of the Comedy Central animated series South Park. It was originally broadcast on March 23, 2005 and was named after and featured the New Zealand singer Wing, in an eponymous part loosely based on her.
Upon hearing that Token has won a contest that will allow him to sing at a Colorado beauty pageant and receive $200, Stan, Cartman, Kyle, and Kenny decide to set up the "Super Awesome Talent Agency" and obtain 10% of his earnings by becoming his agents.
They lose him to another talent agency, however, only to land a singer named Wing, who is the wife of the City Wok owner, Tuong Lu Kim. Recently smuggled into the United States by the Chinese Mafia, Wing has been set to audition for American Idol, and the boys agree to bring her to Los Angeles for the competition.


South Park Spoiler Alert!
(The complete plot for this South Park Episode)


Upon hearing that Token has won a contest that will allow him to sing at a Colorado beauty pageant and receive $200, Stan, Cartman, Kyle, and Kenny decide to set up the "Super Awesome Talent Agency" and obtain 10% of his earnings by becoming his agents. They lose him to Creative Artists Agency, however, only to land a singer named Wing, who is the wife of the City Wok owner, Tuong Lu Kim. Recently smuggled into the United States by the Chinese Mafia, Wing has been set to audition for American Idol, and the boys agree to bring her to Los Angeles for the competition. This venture does not go as planned and instead enter her into The Contender. Sylvester Stallone is impressed with her singing even as she is beaten and gives her a chance to sing at his son's wedding, which will give the boys a 10% share of $4000.
However, by this time, Wing has been kidnapped by the Chinese Mafia for not paying the $10,000 owed to them for getting her into the States. The boys go after Wing to get back their client. Both the Mafia and the boys are unaware of the other's intentions; the boys mistake the Mafia for the Creative Artists Agency, the agency that stole Token, while the Mafia think the boys are a rival group. In a shootout at the Mafia's headquarters, Kenny is killed, and Kyle inadvertently manages to kill two Mafia guards. Stan concludes with a monologue about how Wing is a human being and that people's lives should not be sold as commodities which makes the boys and the Mafia realize that their businesses are dirty and exploit the hopes of others. They all decide to quit and go to listen to Wing sing at the wedding, only to find Token waiting tables, trying to earn enough money to get back home as CAA did nothing for him.
The character of Wing was based on Wing Han Tsang- 曾詠韓, a New Zealand singer of Hong Kong origin. All of the songs the character performs in the episode including the ABBA songs "Dancing Queen" and "Fernando", and the song "Sing" are actually the real-life Wing singing, taken from previous audio recordings.
On the DVD commentary for this episode, series creators Trey Parker and Matt Stone explain that they decided to do a show about Wing after a friend led them to her site. They thought that the whole idea of this singer was either a "super sweet joke" or a "super sweet not joke", but continued to listen to more of her music, especially whenever they were frustrated. Parker and Stone contacted Wing on using her songs, and she had to approve her cartoon likeness before allowing her music to be used. Parker also says he received a letter of thanks from her for the sales boost she enjoyed as a result of the episode.