As I’ve been observed, German guys have high manners in public places. So although they spot a good looking girl, they will just look and not doing any action. This is probably because they are also shy people.
However, the situation will be different when they are drunk. Suddenly they become flirty and brave. So be careful, if suddenly there’s a guy come to you, out of nowhere in public places, asking your name or telling that you are beautiful; then surely that guy is drunk!
No joke in this. At least there’re two times that I tried to escape from these kinda guys!