>>16290462"Niche" in regard to the suit itself might be debatable, as its appeal is more akin to wearing a latex bodysuit than armor really (even with the likely association to tokusatsu shows). Latex bodysuits have been a thing in the world of fetishes longer than internet became a household standard.
The helmet doesn't work for everybody, but I think there's some kind of psychological aspect of it covering the face like it being blocked off makes you want it more.
I had this fetish for years and I STILL have trouble explaining how it works. 