Amber Rose was joined by reality TV stars Blac Chyna and Kendra Wilkinson as she staged her second annual “Slut Walk” in Los Angeles.   The model and ex-girlfriend of rapper Kanye West wore a tiny black outfit for the event which was organized to highlight “sexual injustice and gender inequality”. Amber, 32, was joined on stage in downtown LA by her pregnant friend Chyna, who is expecting a child with Robert Kardashian. Slut Walks have been organized in recent years after a police officer told female students in Toronto in 2011 that women “should avoid dressing like sluts in order not to be victimized” On her website, Amber explained why…