Looking for objective opinions, and will try to keep this as neutral as possible. I have name changed for obvious reasons.
At the age of 15 a girl goes to a nightclub as part of a group of four, including her best friend, her future brother in law (age 23) and her future brother in law's best friend. The girl's sister is away but aware of where her sister/partner are and their plans.
The night is fun, too much (not much by an adult's standards) is drunk and the girl's best friend (who is 16) decides to go home with the friend of the future brother in law. The girl is left with the future brother in law and they go back to his house because it's close by. She falls asleep in his bed and awakes to find he has taken her jeans and underwear off and is 'going down' on her. She starts to cry he trys to kiss her to make her be quiet, while trying to force his penis into her (she is a virgin). It only half works and she is distressed and almost hysterical at this point. He stops and they fall asleep in the same bed.
In the morning he drives her home, coaching her on what to say to her sister. He says no one will believe her if she tells the truth, and everyone including her sister, will hate her for lying.
Whose fault was this?