Isn't it funny that a flood of lewd can explode to this extent from an otherwise mostly innocuous source.
While most ecchi animes, with characters dedicated to being lewded barely has fanarts?
It all boils down to popularity in the end. Sure an ecchi series might have pre-lewded characters but if the source material isn't popular then of course it won't get lots of art. Bowser, however, is a well known character from an extremely popular, if not THE most popular, video game franchise on the planet. Combine that with the internet's love of, "big-tiddy goth girls" and you've basically got a perfect storm that people on both hemispheres can enjoy.
