a) Any person who has an extreme desire to only associate with Asian or Asian descent people -- socially, sexually, etc.
b) a fetish for a certain thing, things/anything Asian.
a) "What's with him/her only wanting to be with Asians? Turned into a real rice monster."
b) "Man, he's/she's totally hooked on that (fill in term such as anime, japanamation, etc. here). Turned into a real rice monster."