You assume that the content of the site is relevant. Do you know this? If not, it's just as likely (from an outside observers pov) the domain is using 'fuck' a

You assume that the content of the site is relevant. Do you know this? If not, it's just as likely (from an outside observers pov) the domain is using 'fuck' as a euphemism for 'have sex with' as it is the one you intended. In the case where the purpose of the domain is irrelevant and the registration of the domain itself (and its publication to DNS) is the speech in question my armchair assessment is this may actually be untrodden ground.