Aachi & Ssipak is a 2006 animated South Korean film directed by Jo Beom-jin and featuring the voices of Ryoo Seung-bum, Im Chang-jung, and Hyun Young.

Sometime in the future, mankind has depleted all energy and fuel sources, however they have somehow engineered a way to use human excrement as fuel. To reward production, the government hands out extremely addictive, popsicle-like “Juicybars” to citizens,which in turn also makes them constipated. Aachi and Ssipak are street hoodlums who struggle to survive by trading black market Juicybars. Through a chain of events involving their porn-director acquaintance Jimmy the Freak, they meet a porn star named Beautiful, who gets a pink ring inside her butt which makes her defecations are rewarded by exceptional quantities of Juicybars. For that reason, Beautiful is also wanted by the violent blue mutants known as the Diaper Gang (led by the Diaper King), the police (most notably the cyborg police officer Geko), and others.

http://www.imdb.com/title/tt0972542/