Cougar allows it

The content available on xHamster may contain pornographic materials.

xHamster is strictly limited to those over 18 or of legal age in your jurisdiction, whichever is greater.

One of our core goals is to help parents restrict access to xHamster for minors, so we have ensured that xHamster is, and remains, fully compliant with the RTA (Restricted to Adults) code. This means that all access to the site can be blocked by simple parental control tools. It is important that responsible parents and guardians take the necessary steps to prevent minors from accessing unsuitable content online, especially age-restricted content.

Anyone with a minor in their household or under their supervision should implement basic parental control protections, including computer hardware and device settings, software installation, or ISP filtering services, to block your minors from accessing inappropriate content.