Some artists slink towards the end of their sets when those in attendance fail to show love. Not Marshall Mathers. Displeased by a San Francisco crowd's insufficient participation, the battle rap-hardened lyricist threw his towel at fans and demanded them to do better. They listened. After throwing out a particular showgoer for disrespecting Detroit, Em orchestrated a call-and-response that reignited the building's energy for “Bitch Please II.” Aspiring rappers, take notes.