[DiscoNinja]

"Content is a king" is one of the SEO myths for me. Many people believe in it and don't question it (almost like religion ).
But if you check for these keywords in Google:
anal porn
ass porn
asian porn
black porn
mature porn
(by the way, all very competitive keywords)
This list could be much bigger, but it is enough to make the point. All the top sites for these keywords are TGPs with just a few lines of text and mostly only one page. How their content is a king comparing to hundreds of millions of other TGPs? Maybe Google has some smart image recognition algo which decides whose thumbnails are the hottest.
I would say backlinks are the king. There are some kind of sites which only take care of their content and not about their backlinks (for example BBC, CNN, etc), but forget about those. In adult industry you will not get many free backlinks no matter how great your content is.