I am no longer angry. I am just giving you a scenario of my first-hand experience. 

-By implying that a female drinking with a male is the open invitation for sex is reprehensible. It has as much logic as the clothing a woman chooses invites sex. Men need to learn to keep their pants zipped up and not assume everything is a sexual invitation. 

"The whole purpose of having those drinks is to "loosen up," after all. What happens later...blame it on the alcohol, not on the guy! Although he may have offered to buy the drink, it was the woman who said "Okay."
-Just because two people go out to have drinks together to "loosen up", it is still not an invitation to have sex. And you cannot blame it on the alcohol. It is the same as blaming it on the gun when someone is shot, or on the car when someone drives dangerously. These are inanimate objects. They are only dangerous when people misuse them.