What happens when 당신 cut off a 뱀파이어 limb. Does it turn to dust is it just gone does it regenerate???

Basically the vampire is still alive

I'm not sure. Maybe the vampire can reattach the severed limb, assuming he 또는 she can still find it. Maybe the vampire grows a new limb. I don't think he 또는 she would be stuck without a limb permanently though.