I once said I'm gonna link this video in here as many times as someone asks, because working with "bad alters" is described better in here than anywhere else I've found. Parts who hurt the body are called persecutors, and they do exist in many systems. Still all parts are there because they try to help or because they're feeling overwhelmingly bad. Their ways of trying to help may not be best ones anymore, but there's always a reason why they are the way they are.
Learning to know them is important. Then you get to know why they do what they do and can help them with their actual problems. Sometimes they don't know why themselves either, but sometimes they think they're helping. Some may just feel so sad and angry they can't cope and they need help. Still, even the ones who try to hurt other parts or themselves, may not wanna hurt anyone. They can try to protect the ways that just don't work (anymore), but they can learn better ways.
Anyway, here's the link:
https://www.youtube.com/watch?v=pZANla33sb8. Just remember this is one example of how they can be, but they can be different kind as well.
Our systems persecutors are tweens from Jules' system. There's many of them and they all have different reasons to hurt themselves or the body outside. The one who has tried to OD many times is trying to get outside help for us, or himself. He wants to go to hospital, because he hopes there could be an adult who takes care of him and he could just rest, and people would understand he's tired and can't go on anymore living adult life. That he would not be treated like an adult, because he isn't. There's several others too, and all have different reason. Some hurt their boy body in inner world, but not the body outside, they may not be aware of outside at all. They punish themselves because they think it's bad to be a boy, or be a boy the way they are, or because they've done something they think needs to be punished. They think that because that's what they've been told before. Some hurt only the outside body, because of body dysphoria that makes them freak out. Some want to feel pain because it calms them down and helps them with self regulation. Some have difficulties understanding and naming their feelings, so they make visible injuries to show they are hurting, they make them for themselves to see and for others to see as well. They all need different kind of help, because their motives are different, but non of them is bad.
Floralie