Don't be tempted to click the link and see because they don't lead to a porn site as implied, most link to a page looking like this:

If you choose to click on the button you just loaded an executable file and it probably carries some sort of virus or the likes.
Protect your computer by downloading a trial offer or free anti virus program for:
WINDOWS
AGV
Eset
LINUX
ClamAV
I'm going to look for a good way to tackle this problem but I'm short of time at the moment. In the mean time, avoid problems by not clicking on offers such as these and get a decent anti virus program installed. It's so important to prevent infection rather than cleaning up the mess after the fact.
In the mean time the spammers will be systematically removed as they appear.