Having travelled extensively in Japan and Korea and even worked in the industry a little... I have to say the story is almost not possible.
1. Condom breaking: well shit happens: but you won't get attacked for it. All these girls have experienced: unprotected sex (guaranteed) and have had numerous condom breaks.
There's an unspoken rule in Asia at least in Korea and Japan that I know for sure: THe customer is always right.
This doesn't mean that you can rape the girl and they'll nod their head and allow it: what this means is that: if you pay, they are there to serve you to the best of their ability. They would never ever go ballistic for your mistake; if you don't know already: Japanese are experts in hiding their true feeling/emotions. If your condom broke, she would have probably smiled and said it's ok, while hastily going to the bathroom to clean up.
2. You getting struck in the face. I've worked as a cashier in some of these places before ... The guys that work as barkers and "guards" are not to be sniffed at. The word used for them can be translated to: "street urchins"? They're not full fledged gangsters, but they come close, some are connected higher up and they move in packs....: they don't have much respect for life and they DO know how to fight. If they wanted you beaten up, a black eye is the least of your troubles. You would have woken up in an alley with plenty of cracked bones.
I myself have been present seeing some super lousy customers get "roughed" up: it's not a pretty sight. On a few occasions the police came: you being a foreigner puts you in a weak situation: all these urchins have to do is say you raped the girl or something.... tough: it's not a fair fight.
3. Girlfriend issues: I couldn't care less about the girl friend situation, but please don't be a baboon. Pleasure districts are fun to go to esp with friends and such... But it's just that: for pleasure. In real life, however much you enjoy these pleasure districts, you have to be responsible. If you don't value your own life much, noone really cares, but why get a nice girl involved?
If you want to be loved, be worthy of it.
If you think you're cool because you go to some massage parlor/soapland while you have a girlfriend, you need to grow up and stop thinking like scum.
4. Running from such places: If you run, it makes you a criminal..... It's a very good chance that they're going to "black list" you.... If they see you again, you might be in big big trouble. If i had been in your situation, and they REALLY are ready to strike you down for that broken condom (which I mentioned is highly unlikely): I would have emptied my pockets offerring double or triple for the service and my sincere apologies ....
A highly unlikely story....
Just my opinion~
Eddytad