i found the kdrama Goblin /Guardian -Lonely and Great God disgusting for that reason. If you knew someone as a child then its pretty gross to fuck them later in life even when they are grown up. A lot of people defend that show.
This one is bad in that he fantasised about someone who was a child.
BUT throwing that term "pedo" around because we disapprove of his fantasy, and want to police peoples fantasies only makes the word less meaningful. And using that word as a witch-hunt or to label others for actions we find distasteful is harming actual victims because that word isnt taken seriously anymore.
We may be disgusted at his fantasy but he didnt do anything illegal.
He didnt have sex with a child so it doesnt make him a pedophile.
I've read so many manhwa manhua and manga in my life and this is the worst, first time ever i've read the worst the storyline is directionless and disgusting because it means noah has been a pedo all this time. He even imagines "a child" while fucking someone else