A person who oversees a site and moderates or removes postings is called a

A sysop, short for system operator, administers an online site or forum and holds the power to moderate, edit or remove user postings.

A judge decides legal cases in a court and has nothing to do with running a website.

A narrator tells or voices a story and plays no administrative role online.

A censor suppresses objectionable material broadly, but the term for the person managing a specific site is different.

The role dates back to bulletin board systems where one operator ran the whole board.

Modern equivalents include forum administrators and community moderators.