Three men with whom I was romantically or sexually involved have tried to fight to defend me. I think quickly and act decisively, so only one was able to follow through. I prevented the other two. The one I couldn't stop was successfully stopped twice. He ended up having to pull me away from an altercation instead on one of those occasions, but I think I saved the other guy's life both of those times. He had touched me sexually when I had explicitly said not to, and the man I was with seemed ready to kill him.
The two times he did fight, were weird. The first time, I was alone in a dark cabana while dude went inside to use the restroom. Some guy came outside, having walked past the actual rest room, entered my cabana, and started peeing next to me. I'm not sure he knew I was there. My dude came out, beat his ass, rubbed his face in his pee and called him a "Bad Drunk!" scolding him like a wayward puppy. I ran inside to get the manager. He told the drunk guy to clean up his mess. Gave him a hose and some pine sol.
The other time, we were at the rooftop pool of a sex club, and someone photographed me knowing I did not wish to be photographed and that it was against the rules to even have a cell phone on the roof. Dude dangled him off the roof. Told he was going to leave, and that he could walk down the stairs and never come back, or take a short cut over the side. He allowed me to take the SD card and throw the man's phone off the roof. Destroying his phone was very satisfying.
Last year I was out with a dude and some guy tried to kick it to me while Dude was at the bar. I declined, of course, telling him I was on a date. Later, he came by and threw beer bottles at us. I felt Dude's energy change, and kept trying to keep him out of trouble, but he just gently peeled my hands off him. But before he could fight that guy, I found a security guard and had the other guy kicked out of the place.
An ex seemed like he wanted to fight some guy I was befriending to do karaoke with. I declared that we were now too drunk and I put us in a cab and went home.
Most of my stories about dudes getting violent involve intoxication. Sober people have way more chill.