It would be a sixth degree burn
Step-by-step explanation:
First degree burns happen on the outer layer of your skin, they heal on their own. An example of this is a sun burn.
Second degree burns burn the outer layer of the skin and the dermis, which is the layer underneath the epidermis (or the outer layer of skin). They normally leave a scar.
Third degree burns destroy all of the layers of skin, they burn hair follicles, sweat glands, etc. You will be hospitalized.
Fourth degree burns burn into fat.
Fifth degree burns burn into muscle and
Sixth degree burns burn into bones.
Hope this helps!