A little help needed

On my blog, I can see where traffic is coming from.  At least the top ten or twenty sites on a given day.  So if a bunch of people suddenly come over from a given website, I can see it.  If it's one I don't recognize, I click on the link and it takes me to the location.  Sometimes it's some goofy generic place.  But sometimes it's a legit site.

All of a sudden, I'm getting traffic flow from a site that is, well, adult oriented.  That means traffic is coming from there.  It's an intro page (If you are over 18, click here), so I haven't gone in to see why my blog is sending traffic here.

If anyone could help by telling me how to block traffic from this site, or somehow get it cut off from sending things here, I'd appreciate it.  Not only because I don't want the substance of the site coming here, but because I can't help but guess there is more to it than just readers at an adult site suddenly interested in my ramblings about the latest issues or my obsession with fall.

Thanks.  Feel free to email me with suggestions.

BTW, it seems to come over under a variety of names, but they all go to the same location.