Otaku 

Otaku is a Japanese term used to refer to people with obsessive interests, particularly anime, manga, and video games.

Etymology

As an honorific second-person pronoun

Otaku is derived from a Japanese term for another's house or family that is also used as a honorific second-person pronoun. The modern slang form, which is distinguished from the older usage by being written only in hiragana or katakana, or rarely in rōmaji, appeared in the 1980s. In the anime Macross, first aired in 1982, the term was used by Lynn Minmay as an honorific term. It appears to have been coined by the humorist and essayist Akio Nakamori in his 1983 series An Investigation of "Otaku", printed in the lolicon magazine Manga Burikko. Animators like Haruhiko Mikimoto and Shōji Kawamori used the term among themselves as an honorific second-person pronoun since the late 1970s.

From the works of science fiction author Motoko Arai

Another source for the term comes from the works of science fiction author Motoko Arai. In his book Wrong about Japan, Peter Carey interviews the novelist, artist and Gundam chronicler Yuka Minakawa. She reveals that Arai used the word in her novels as a second-person pronoun, and the readers adopted the term for themselves.