I was thinking that too! I feel like Mare gonna grow up a lot faster than Maris will.... and I'm hoping Mare will love Maris a lot since he has such a cute big yet small brother who obviously adores him too!!
... aren't there some cases where humans were rised by demons (and the environment) and they got special skills or became more demon than human... couldn't that happen here?
Like superman and the earth? That would be really cool too, but I'm not really expecting so, since the charm of the comic is the fact Maris is a human taken care by demons
As long as he gets a longer life, I'm satisfied ^^
P r e t t y s u r e mare will grow up faster than Maris, since demons have a gestation way shorter than humans is just normal for their growth to take a shorter time.