Corey Feldman -- Sued for Being a Horrorble Person

Corey Feldman NEVER SHOWED UP to a horror film festival in Pennsylvania last year ... and believe it or not, people are actually upset about it.

Feldman -- who starred in a couple of "Friday the 13th" flicks back in the '80s -- had been sued for failing to appear at the 2009 Eerie Horror Film Festival ... AFTER he accepted a $5,000 payment.

Now, TMZ has learned the court ruled in favor of the EHFF -- and has ordered Corey to fork over $8,149 for the show fee, legal costs and interest.