User blog comment:NibiruMul/What do these terms mean?/@comment-3991308-20151217213119/@comment-11163511-20151218005557

Well, according to the Transfomers Wiki (which also uses these terms), prose-only refers to a character who only appears in written works (like Zena said), but fiction-only characters also cover characters that appear in the media as well, the term refers to any character that doesn't appear in merchandise.