That's messed up and probably not legal. I'd check with them to see what it's about if you get nowhere check with ICANN.
The whois is odd too, says it's registered yet says there's no match in the db. something is not right.
Maybe it's because it's offensive, but I don't think a registrar can do anything about that, a domain is a domain, and I've seen much worse ones. The content of the site hosted at it is a different story and a host could shut it down depending on their rules, but don't think a registrar can do that.
Name Server: NS1.SUSPENDED-FOR.SPAM-AND-ABUSE.COM (has 8,728 domains)
Name Server: NS2.SUSPENDED-FOR.SPAM-AND-ABUSE.COM