Breaking engagement before marriage

My friend got engaged to a girl 1 month back. Marriage is planned this November. But after the engagement he realized that they are absolutely not compatible. He can't even imagine his life with her. His expectations from his life partner are way too different than what she actually is, so he is not at all attached to her yet. they kissed and touched private part things each other. they have kept making agruements and misunderstandings frequently. There wouldn't be any point in marrying if he is not happy as it would ruin both of their lives and career. He is about to cancel the marriage. He has conveyed this to his family and they have finally agreed to do so. He is ready to apologize to them in whatever manner they want him to. She still traps him in her life without any reasons and her family still push her to marry him. she keeps irritating him and his career though. Now the the biggest worry is that can her family file a case against him? what makes them leave him immediately? she and her family need to realize that their relationship does not work out and should cancel the marriage right now without any plan to file a case or to harm etc. I do appreciate your help to answer this question. Thanks