There is no evidence to suggest you are in any more danger from a man who recently came to the country from Afghanistan than you are from a man called Dave who grew up in Barnsley.
Oh yes there is. According to the German stats, the recent arrival from Afghanistan is sixteen times more likely to rape you than Dave (or indeed Hans, as it was a reference against rates of sexual offenses by German men).
There have also been numerous threads on here about women finding it uncomfortable travelling to places like Egypt, Morocco or India due to street sexual harrassment. These men don't magically behave when they get here - in fact the opposite. They are bored, away from the social restrictions of their home countries, have no stake in or care for the communities they are now living in, no access to willing female companionship, and they egg each other on, as seen in the Brighton beach gang rape case.