Borrowed from Japanese, otaku refers to a person who is obsessed with manga, anime, and other forms of Japanese or East Asian popular culture.
What does it mean when someone is an otaku?
: a person having an intense or obsessive interest especially in the fields of anime and manga —often used before another noun otaku culture.
How can I impress an otaku girl?
Impress her by acknowledging those interests. Give her gifts that are related to the things she loves. Otaku girls like to be romanced, but standard “cookie cutter” actions only scratch the surface and fail to address her as an individual. Keep in mind that your gifts do not need to be expensive to make an impression.