I couldn’t find the police guy at the top when I got there but realized that its not a legal issue and that there’s nothing I could really do legally.
Casual Harassment of Young Women in Sri Lanka
Sanjiva Weerawarana

Even though it’s not really a legal issue, letting the police guy know would really help, as they could get fined for drinking in certain public places (not sure if that applies here in Sri Lanka though)