オタク or ヲタク
Can be shortened to "ota".
The Japanese word for "geek, nerd, enthusiasts."
Example of Otaku Characters
- The lead and his network of supporters on Densha Otoko
- Most the characters in Hikounin Sentai AkibaRanger
- Most the leads in akihabara@deep
- Robo in Sexy Voice and Robo
- Kirino and her otaku friends in Oreimo