Thrill kill sounds like a synonym for killjoy.
But the forum is depressing and boring without her.
I had a dream that she moved to a hidden subpart of the forum that was all screwed up with HTML leaking out into the page. Whenever you tried to scroll up it would scroll down instead. It misbehaved oddly. It was like regressed-ish. And Thrill Kill was there all alone and she was just posting by herself. Nobody else was there, well except for me but I was just watching.