One that posts useless drivel in a forum for the sole purpose of raising his post count.
I wish Luke would post something useful some time. He's such a postitute.
Excessively posting random statuses and links on Facebook resulting in friends hiding or deleting you to prevent further viewing.
"Did you see what Mandy posted just now? She's on a rampage!" "No, I was tired of constantly seeing her postitute herself on Facebook, so I hid her from my newsfeed."