An obsessive fan with an unhealthy, highly expansive knowledge over something. Otaku come in many flavors, but one thing can be said for each and every one of them. They've each staked out their own favorite thing, and they obsess over it relentlessly. Regardless of other intelligence, an otaku will have an obsessive, unhealthy, and almost encyclopedic knowledge of their chosen topic. There are almost as many flavors of this type of character as there are things under the sun,