And just to point something else out, the fact that you consider this harassment is just....mind boggling to me. Are you honestly that ignorant to believe 9 people in a single apartment at 10PM talking, doesn't warrant them to make a complaint? Being a "foreigner" who "doesn't know the rules" is no excuse for completely lacking the common sense of being a decent neighbor.
Honestly, you should be thanking the complex's security for not calling the police right away.

