Please talk to your parents or a trusted adult in your real life. Your sister should not be acting out like that. Obviously, it's disturbing to you and I'm concerned about your sister as well. I have concerns about the reasons she may be acting out in those ways. Please reach out for help. It will be scary to talk about it, but keep reaching out. If the first person you tell doesn't believe you or doesn't think it's a big deal - keep telling trusted people until someone takes you seriously. You are worth someone taking care of you and helping you (and your sister) with this situation. Best of luck to you.