German students fence for honour and discipline
10 September 2013 Last updated at 23:04 BST
Nils Hempel, 26, values his friends as much as any man but perhaps never more than when he is slashing at their faces with a sword.
A law student at Humboldt University from Bremen, he belongs to one of Germany's oldest all-male college fraternities, the Corps Marchia Berlin, in the German capital's well-heeled suburb of Dahlem.
Corps members may make up just a few per cent of Germany's student population but their alumni are over-represented among chief executives of the country's companies.
BBC News asked Mr Hempel why he and his fellow students cross swords in the mensur - a form of fencing much like a real duel - and was allowed to film the swordsmen in training.