In Senegal, when concerts or wrestling matches or any event where thousands of people are gathered in a tight space, come to an end, the place will empty in seconds. Patient people- not naturally disposed to hurrying- who have waited quietly for five hours to see one man throw the other down, or angry 20-somethings who have waited all evening for their rap group to come on stage, will suddenly be gripped by a fury to get out of the stadium, ignoring any encore or post-match activity, and will scatter chairs, climb over people, stampede: anything to be out of the stadium in seconds. Watching it, it's like someone pulls the bath plug and the whole world just drains away.

I've never understood it myself. J. and I were caught in a stampede at the stadium after one wrestling match, having sat all afternoon with the docile crowd who suddenly leapt to their feet and careered down the stands to push through the small exit door. In Ziguinchor, I asked T. what it was all about.

"We call it Se-tan," he said. "When the music is playing, Se-tan stands still and people are safe. But when it stops, he comes back again so people hurry home."

Se-tan. Satan. I get it.