The story
From weeaboo, a nonce word invented by Nicholas Gurewitch in a Perry Bible Fellowship comic, later arbitrarily used by the 4chan website as an automated replacement for wapanese in users' posts.
Etymology from Wiktionary, CC BY-SA 4.0.
-aboo
Today it means: A suffix combined with a noun to create a word for a person with an intense and/or unhealthy fixation on the referent of the noun. Full definition →