>>100891274>Is The Things THING made of stone too?
No part of him is "made of stone." It's instructive to think of him as having an extremely severe skin condition where his outer layer of skin is hardened into this extremely thick, rugged layer of armour. The underlying tissues and muscle are still flesh and blood, albeit extremely strong and tough flesh and blood, thus his superhuman strength.
Now here's the more unsettling question: If we envision his penis in its flaccid state as looking more or less like the rest of his body, with cracks between orange plates which are otherwise basically flush with one another, imagine what it's like when erect: I would imagine that as the underlying flesh becomes engorged, the plates essentially spread out sparsely along its length.
See this illustration of one of his fingers in a hypothetical situation where it became massively swollen as an example of what that might look like.