How do I delete my account?

I joined an online forum that does not allow members to unsubscribe, or delete their postings/accounts. Ped a certain date, editing is no longer allowed. I've tried contacting the moderator but this has not worked. According to the terms of service, the forum now owns my posts and account. I read this when I joined but I did not know that I could never change anything or remove myself from it. I know it is possible for them to delete posts because it happens when someone submits inappropriate content. Aside from posting profanity to get attention, what can I do?