I wouldn't be offended if someone called me an otaku," says Koichi Nakayasu, ". . . because I am."

"Otaku" and proud -- and he's not alone. The number of hardcore manga and anime fan otaku probably number in the hundreds of thousands.

If you include occasional consumers of otaku culture, maybe millions. Otaku culture has even spread abroad -- becoming one of Japan's most successful pop-culture exports.