The fact that the animals can die, especially if you didn't know this and neglected to feed them after a harvest.
The Scion of Purple, encountered after drinking an Essence of Purple.
One area of Naraka has a warning to not go there if you're squeamish about gore. It's got tomatoes and bloodstains, and isn't too bad, but the fact that a warning was needed says something.
Tear Jerker: The end of the game, especially the Goodnight Groddle Lullaby that first played when the beta test ended.
What Do You Mean, It's Not for Kids?: It's a cutesy, brightly-colored, non-violent game with talking wildlife. There are also drugs, alcohol, and plenty of sex jokes. Many new members make the mistake of thinking it's a kid-friendly game even though you have to be 14 to sign up.