TL;DR: Guy defends a woman and loses a testicle in a fight. Woman is not appreciative.

http://redditlog.com/snapshots/161681

Relevant portion:

"How did you lose your testicle?"

"Defending a small girl from a drunk guy that was attacking her. I intervened and the ultra intimidating 5 ft 5 110 lbs me got my ass handed to me."

"Well, hopefully the girl you saved can now give you a handjob for your efforts"

"No, actually, she shouted at me afterwards. I was well annoyed and my nuts were hurting"

"Wtf why? What a thundercunt"

"Maybe she was just shaken? I dunno..."

I feel bad for the guy - he was probably fighting a much larger opponent. Losing a testicle is a huge price to pay for being a white knight.