For the rope burn I would use aloe vera, such as in the products for sunburns.

More concerned about having a rope around the neck. After working in the emergency room and as am EMT for years, it is amazing how many unintended and unplanned accidents there are surrounding this, and they all thought and truly believed that they had control of the situation with fool-proof back-up plans. Please reconsider doing this because the repercussions are permanent major injuries/disabilities to death. It is not worth it. Wish for you to stay safe.