Her parents were divorced and living with her mom was stifling her. She wanted to live with her dad. She was just sixteen, though, so it looked like she would would have to endure two more long years before she could investigate things sexual. On a rare weekend visit with her father she asked him to take her on her first romantic date. In determining what "romantic" meant some investigation revealed she did not object to being naked with him. She didn't object to letting him breed her, either.
When the parents are away for the weekend we play games together. Tonight was my turn to pick and I chose Truth or Dare. They were initially skeptical, but after things got spicy we started having fun.
His daughters had escaped with a pack of grass when a party they were at was raided. To protect his daughters he had to help them dispose of the evidence ... he did't expect what that would result in!