Hope you don't mind i say this, because, he didn't respect your

sister too much, so he didn't even bother to make up some lies like "I love you, i love you so much"...etc, He knew even he told her the truth, she would still come back to him. My daughter used the word "manipulate" means the that the guy wants to "control" her. She should just leave him right away

BTW, my daughter typed the last sentence

Good luck to your sis