Let me tell you what should yo do

Become selfish

Yeah thats the right answer. First go and tell the police about her/him( whatever you wanted to write). SAVE YOURSELF FIRST!!!!!!!!!!!!!!!!!!

GO AND FILE A REPORT IN POLICE STATION, GO AND TALK TO HER/HIM PARENTS AND TELL THEM EVERYTHING. BE SELFISH. SAVE YOURSELF.PLEASE.

Same thing happened to my friend, who was helping a depressed girl because he was nice to all people. But the girl commit sucd*. Her family didn't know about her depression. When her call history was recovered, the family blame my friend. He comes from a typical middle class family, it shocked his parent that police is taking their son from his own house. Around 6 month my friend got completely waste and the regular visit of police to his house also creates false rumours in neighbourhood.

If you want to help him/her then do what you want to do but please first inform her/him parents and authorities. Please don't end up runing your life in hope to save others life.