Recently, the number of "follower sellers" has increased dramatically. They offer Twitter users to increase their number of followers in exchange for money. I didn't know about those services earlier, but they have started to intensely use spam messages for advertising recently. There are services like fast-follow.com and buyfollowers.eu.
I never approve those web services. I think it comprises some kind of cheat. You give some money and you get 100,000 followers. Who are these followers? Fake accounts? Or real users whose accounts are abused? Is it legal to do this?
In short, can you provide some info about this business and how their system works?