Currently gao is assigned as artist type, but this one overlaps with usual gao tag usage, i.e. characters making "raawr" (gao in japanese). To make situation more complicated there is chara tag gao_(rhapsody) which probably means chara from one of game (? not quite sure about that). Fortunately it seems all the gao_(rhapsody) posts are tagged correctly.
I suggest changing gao to gao_(artist) edit adequate posts, then downgrade gao to general one. Very little work to do, I could do it right now by myself but maybe it'd better if I ask on the forum before that.
Updated by a moderator