You may not know what tokusetsu is, but you must know what Ultraman is. Ultraman is one part of the whole tokusetsu, at the same time ,as you know, Godzilla also is a part of it.
Like Marvel and DC’s superheroes in western culture, heroes in tokusetsu dramas are the heroes of some Japanese. Do you remember Crayon Shin-chan’s favorite hero? He could also be one of the tokusetsu heroes.
And the most popular tokusetsu series in Japan right now might be Kamen Rider and Super Santai (Power Rangers)
And this kind of otaku is not only male, but also female.
Reference,
http://www.japan-talk.com/jt/new/20-greatest-Japanese-superheroes