It's Jotaro. It'd take a while to explain how I know. But I know it.
He constantly attacks just the idea of Christianity and even attacked me for my religion. He told me my entire religion was stereotypical and homophobic. He also frequently posts anonymously to keep from being blamed or caught doing things. He did it in order to avoid me knowing he was posting about me. It may just be a hunch but it's a pretty good one, seeing as he has also posted anti-christian memes there before and has said that we should spam them.