Note: I do not represent Cloudflare or Cloudflare’s views. You should read their TOS and Abuse policy.
Note that based on the abuse policy and TOS listed above, Cloudflare does not prohibit pornography from being hosted on its service. The only exclusion is underaged or non-consensual porn, in which you should immediately notify the website operator and only contact Cloudflare if the operator fails to take down the video within a reasonable time frame.
(My opinion): Instead of requesting takedown of pornographic websites, I suggest making sure the website has the Restricted To Adults (RTA) label somewhere on the page (usually found in the footer). This will allow parental blocking programs to safely and reliably block websites that display age-sensitive material. If a website does not have this when you think it should, you should contact the website operator about getting the label implemented.