Does content seo help a domain (as a whole)?

For instance.. I have a niche porn site. The pages themselves will be light on text content because.. its porn. I do have a subweb that is a blog and have a few 1000 word articles that talk about the history and psychology behind the niche.. in a nutshell. Does having lot of that kind of content help the domain as a whole rank? Or just the blog pages. Im thinking about having a few more articles written, but just not sure if it even helps. I technically don't really give any fks if people visit the blog articles... its just for domain seo.