A stone's throw from Kenya's largest informal settlement, a young woman glides down a spotlit catwalk, her delicate white dress at odds with the fake blood splattered across it and the tape covering her lips reading: "Stop, silence, gender-based violence".

The annual "Mr and Ms Kibera" pageant in Nairobi, gleefully attended by hundreds, is about more than just the contestants' looks -- it provides a much-needed platform for expression and protest.

For many of those taking part, the cool August evening was a chance to voice support for youth-led demonstrations and freedom of speech or to condemn violence against women.

Gender-based violence in the east African country has been labelled a "femicide" by activists, who have urged the government to act.