Step siblings. But I've seen some interest in a patch so maybe someone will make one soon. If they do I'm sure it'll turn up here before long.So, I just started, and in the conversation at the beginning they say Rex is the MC sister, but we don't have an incest tag, is it because she is not a blood related sister, because they are not going to have sex in the story, or is it because you are only putting the tag when you add a scene between them?