answer to establishing copyright for a character or creative work or character

In answer to establishing copyright for a character or creative work:

For legal backup reference to establish official US/world copyright, LOC is the way, especially if anyone is suing _

http://www.copyright.gov/eco/  online Library of Congress registry;

http://www.copyright.gov/forms/formpa.pdf for performing arts copyright (film, TV, music, choreography, screenplays, etc.);

http://www.copyright.gov/forms/formtx.pdf copyrighting literary (fiction, nonfiction, catalog, textbooks, etc.);

also, for establishing ownership within US entertainment there is WGA http://www.wgawregistry.org/webrss/

LOC has the greater weight and world reach.