In a different question it was asked if the blood of a non-Kosher animal is forbidden under the same issur that blood from a kosher animal is forbidden. It's brought there from that Rambam that:
ודבר מפורש בתורה שאינו חייב אלא על דם בהמה חיה ועוף בלבד, בין טמאים בין טהורים
It is explicitly in the Torah that the prohibition is on animal and bird blood only, whether Kosher or non-Kosher
It's also brought from the Rambam that:
ודם חגבים ודגים טמאים, אסור--משום שהוא תמצית גופן, כחלב בהמה טמאה
The blood of locust and fish which aren't Kosher is forbidden - because it is part of their body, like fat of a non-Kosher animal
So we see at least that blood is ossur based on the fact that it comes from a species that is ossur -- and I'm assuming min HaTorah. Would the same be true for all other parts of the animals body (like skin, bones, etc. If a person would "eat" them?) Would eating them constitute an issur min HaTorah or is it only on the meat itself and (according to this Rambam) also on the blood since both meat and blood are generally "consumable" while eating the bones, skin, etc might not be ossur min HaTorah as they are not generally eaten?