Hi there and thank you for sharing your concern. It sounds like you are experiencing a difficult situation. As a parent, we want to protect our children from harm. We do our best to educate them as well. Unfortunately, teenagers can be very difficult to reach since they are striving for independence yet lack the wisdom and experience that comes with it. While you have parental authority over her exert it. You do not have to agree to her moving in with the 27 year old as long as she is a minor. If she defies you and you feel like you have no control over her actions, she may have to end up learning the hard way. This is not what we want for our children, of course, but when you've tried everything you can to make them aware and they still don't heed your advice, experience tends to be how they end up learning (often the hard way.) You've already tried contacting police social services. Unfortunately, options are limited. Love her through it if you can. Be there when she needs you. Don't allow her choices to make you feel as if you have fallen short as a parent. May the situation work out for the best. Let me know if I can be of further assistance!