Tumblr is pretty funny, I recommend reading the terms of service for the little jokes included:
Gore, Mutilation, Bestiality, or Necrophilia. Don’t post gore just to be shocking. Don’t showcase the mutilation or torture of human beings, animals, or their remains. Dick
Uploading Sexually Explicit Video. You can embed anything in a Tumblr post as long as it’s lawful and follows our other guidelines, but please don’t use Tumblr’s Upload Video feature to upload sexually explicit video. We’re not in the business of hosting adult-oriented videos (and it’s fucking expensive).