People on social networking sites such as facebook that sit around reading posts then proceeding to shit all over them. Typically seen when someone makes a post or status update containing some exciting news or an announcement. Then along comes the post pooper and posts something to destroy the mood of the post.
Ash: so I've decided I'm going back to school in the fall :)
2 hours ago via Facebook for BlackBerry · Comment · Like

Post Pooper: Hi ash... Not that my opinion counts for much however, proceed with caution. You have bitten off a lot lately. New job, new business (selling purses) and now school. I think you def go back if u want to go I just caution not to bite off more than u can chew all at once. Love ya
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