Before you say, Plan B is not a rapper but raps in his songs.Lil'Wayne and Eminem might have sang/made a chart-hitting song called "No Love" but that doesn't make them friends(they are actually friends).Plan B's "Stay Too Long" contained swearing and rapping(both what you find in any of Eminems songs).Eminem is probably about the best rapper in the world (my opinion,not a fact).