A type of an obsessive anime fan (otaku.) Moe-fags are not looking for a decent plot or adult dialog, they are interested mainly in characters and typically have sexual interest in them.
Another slang for the already slang "motherfucker"
Pretty much spelled how some people pronounce it.
Other synonyms include mofo, moefuga (mispelling), mafacka, etc.
Jake- Mayne, that kid just threw a rock thru mah car's window! I'ma get that moefugga gudddd!