Absence of evidence doesn't always imply evidence of absence... The girl could have been too intoxicated to fight back for all we know.. She could have laid down helplessly while Mr. Nepal was thanking his luck for being a taxi driver... I'm not saying that the girl was all innocent, but the girl's physical state was not that great for a person in his sane mind to fool around with... Moreover, even if iit was agreed upon, he shouldn't have trusted someone that easily... Sometimes you have to pay a big price for taking a hasty decision and preferring the amusing road than the safer one... And you don't need to be "psycho" to rape a woman.. Sometimes a drizzling blood rush down the "hardnosed canal" and a feeble mind could trigger the evil thought as it seems to be in this case....