From South Korean animation group, Studio Flying who created the bizarre and visceral Aachi & Ssipak, comes this demo from 2005 titled "Forest of Nemi". It's available to view HERE. It seems to be the reminants of a scrapped project that has since been overtaken by their new production, Dokkaebi, which is based on Korean mythology.
And in case you've missed it, here is the trailer and first five minutes of Aachi & Ssipak set in a future where the most important fuel is excrement and the government tries to control its citizens with addictive popsicles and monitoring devices:
Twitch Article (Source)
Aachi & Ssipak site
Dokkaebi - Wiki