"First, they cover the pictures, because the blood can go all over," Hans began. "I saw a lot of duels, and fuck, there's a lot of blood." Fearing reprisals, Hans, a student, insisted on using a fake name. He also asked us not to mention the fencing fraternity he defected from in Heidelberg, Germany. "It's not a public thing," he said. "You don't go around telling people, and there are no videos of a real duel."

The secret duels, conducted by a small number of university fraternities in Germany, Austria, and Switzerland, are all that remain of a once widespread practice called Mensur. In a Mensur bout, fencers display their valor through stoic endurance of an opponent's blows. From the 19th century on, the practice flourished across Europe, before quickly declining after World War II. "In the past," Hans noted, "only high-borns were allowed to carry weapons, but since students were in danger of getting robbed on their travels, the king decided to let them wear weapons too. Of course, they were like, 'Oh, cool. Let's duel each other.'"

There were many fatalities—typically caused by sword thrusts to the lungs or heart. The loss of eyes, ears, and noses was also common. In 1566, famed astronomer Tycho Brahe lost his nose to a fellow student's sword. For the rest of his life, the Dane wore a brass prosthetic.

Heavy casualties led to the adoption of chain-mail suits, eye coverings, and nose sheaths. "Still," Hans said, "if a sword gets trapped under the nose guard, it'll cut your nose to pieces. That's not so nice. You can also lose a piece of your [scalp] with your hair on it. I saw guys faint.

"When the face is [lacerated]," he explained, "they pause to stitch it without anesthetic. A doctor is always there. They don't use too many stitches, because in a duel for honor, the man with the most stitches loses. Sometimes there are these huge cuts with only two or three stitches. It makes the scar a lot bigger. Back in the day, they ripped the wound apart, or put horsehair in it, so it would infect and be bigger. It was a big deal for men from the upper society to have a scar."

In addition to being badges of courage, the marks, known as Schmisse, are often seen as aphrodisiacs. "There's a famous quote," Hans said, "that if you have a scar on your face, it's a sure thing to get a girl. And the worse it looks, the better it is for the girl." A 2009 study in the journal Personality and Individual Differences supports that conclusion, finding that women favor men with facial scars for short-term relationships.

Duels of honor are customarily initiated when one fencer tears his business card and hands it to an opponent. As Hans noted, there are always plenty of opportunities to make enemies. "Fraternities are constantly having drinking competitions against each other. You have to puke. They actually have buckets for you to puke in, because your stomach only has a certain amount of space. People always talk bad to each other when they drink."

After a year as a pledge, Hans earned the right to participate in his first duel. "Several times," he said, "our swords got stuck, and the other guy hit me on the head with the flat side of the blade. You're not allowed to move, but I got a little bit scared and flinched. Everyone said, 'That's very dishonorable.' Even if you see it coming, you have to take it like a man. There are always five hits, and then it's the next round. You have 25 or 30 rounds, depending on the duel. We got stuck again on the next round, and I moved again, and they took me out of the duel. They said, 'You have to clean your honor in another duel.' I was like, 'Peace out.'

"They say it's not about winning; it's about standing up for your fraternity. They say that honor is important, but no one really cares about it. I have no fencing honor anymore. I can live with that."