An Incubus needs to feed off human energy. It wouldn't make much sense for them to be born/brought to live as babies or age the same way humans do. We also know that divine beasts are usually born complete so I guess it's the same for demons. In human years he would probably a twentysomething year old.
He's ten years old because he's supposed to be a rookie, not a child.
Yes... I hear what you're saying BUT the mangaka would have introduced him as immature, literally anything else BUT chose to add the age, It made it cringey cause now it's always in the back of my mind plus his behaviour screams child... No matter what, 10years old human child is the same as a 10years child in the Incubus world.
I'm I the only one that is bothered by the fact that this incubus is a child.. 10years old.. why did the mangaka do this? It's about to spoil the manga for me. I'm here for grown-ass men, not kiddies
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