Twitter is full of spammers. Some people will use any hot girl display image, some people will use username like freeapps, facebookapps, newapps, divxmovies, wptips, wordpresstips, facebooktips, twittermarketingtips, newtools, freeiphoneapps etc. to attract new followers but those might be spammers who will just throw some random links at you from time to time. You hope that these new contacts would provide you some useful info and connect with you but those are just sheep. Black sheep indeed. Alright here are some tools which will help you to take mass or bulk actions. You can follow all people who are following you. I would recommend to select follow all who are following you. Look at their display image and followers and then check their box. These tools will also facilitate you to mass/bulk unfollow who are not following you back. Tension is gone. Relax and hit bulk action button. Flush all black sheep.