I'm looking at a post from Kadath that states that "paid content is DNP". In the description of their art that I want to post they state that the work was a commission (they paid for it).

I'm confused here about the paid content aspect. Is this content that the Kadath commissioned from another artist, or content that they were paid to do that is DNP?

Paid content means that you yourself have to pay to see it, for example some physical print or patreon content, not that someone else has already paid for it to be created.

Thanks for clarifying.