What is an Otaku, a Wapanese, and a Weeabo?

There is a lot of slang to describe foreigners obscenely infatuated with Japanese culture, but these are the definite three most common terms:

An otaku is a Japanese geek, usually emerged in video games, collectibles, anime or manga or all of it.

A wapanese is derogatory for a foreigner who desperately wants to be Japanese, dress like a Japanese, speak like a Japanese.

A weeabo is a non-Japanese person who despises his own kin and culture and is shamelessly obsessed with everything Japanese.