>>718321084
Well first, the hole has to be shallow because of the aforementioned metal frame underneath the layer of synthetic skin and flesh, so sticking an erect cock in there is gonna meet with some serious resistance very early on. Second, what I meant by "functional" isn't intercourse but rather if Light's creations do things like urinate. We know they often drink liquid and can even eat, but I haven't the foggiest idea if they even produce waste much less how it's eliminated. I doubt Inafune gave any thought to this whatsoever, so your guess is as good as any.
One might say: "Then why model that feature at all?" I think the answer is the same as all the other pointless features that I mentioned. Because that's what humans look like under their clothes. And Light was passionate about making human-like robots. They definitely have butts, so really, why wouldn't they?