What is a Weeaboo, and do I even want to know?
it's a japanese constructed slang word that literally means 'foreign lover', as in a paramour from a different culture.
in modern parlance it's really pretty much what the picture shows, someone with too much focus on anime instead of the culture as a whole. It's on par with the grownup men collecting my little ponies, imo.
Orientophile is too cultured for them, Otaku implies some technical understanding, so it's pretty much stuck with the word that the whores use for their regular foreign customers.