I think that he think that calling the cop will not help the situation because it seems like the guy is rich and he can bribe people in the police department to not get caught or he knows that the guy is crazy and if he call the police may actually hurts his sister. I understand that you should call the cops but the cop in Asian are not really that trustworthy or reliable compare to the one like in America/Europe.
I'm just 100% annoyed at him at this point, his sister (that he's trying to 'protect' by serving himself up on a silver platter) clearly has more balls than him
Tsk. Don't be a weak bitch and take the guy's crap. Call the cops on him, say you have reasonable doubt that he's holding your sister against her will. Both of you can verify that. Don't tell me you're actually gonna go to his place -_-