The Bartforts considered naming the baby Damien, but eventually switched back to Leon.
For some time, animals were afraid of the boy, but otherwise, he was an ordinary, healthy kid.
Yet, when Leon turned five, he changed overnight. He now looked at other people like an adult. He knew things that he should not, and he had skills that no person on the whole island could teach him.
Zola gave him a scolding when she first met him. Just as she started, a large black dog appeared and stared at her. She committed suicide the same evening.
His brother Nick watched all that for a while, until he was sure what was going on.
Leon noticed a trace of fear that now haunted Nick's eyes and followed him on his morning walk to the woods near the edge of the island.
Nick tried to hide behind a large tree, but his younger brother was not fooled.
"Why are you running away from me, Nick?" Leon asked his frightened brother.
"I know who you are."
"You do?"
"Dr. Warren knows. I overheard him talking to Dad. He said that... the Devil could create his image on Earth."
"Then say it, Nick. Say it. Out loud."
Nick had to gather all his courage before he managed to blurt out, "You are an isekaied Japanese person."
"Yes, Nick, I am the Devil's son... wait, WHAT?"
"You are an otherworldly being that transmigrated to this world?"
"One may argue that being born by a jackal does not exactly fit the definition, but let's go with transmigration."
Nick went on, "You possess strange powers that will allow you to rule the world?"
"This time, I was thinking about using some ancient Old People weapon."
"You want to marry numerous noble girls, unlike normal people who take peasant concubines?"
Leon shrugged his shoulders. "Sure, it is a time-honored tradition for us spawns of evil."
"See? Those are sure signs of an isekai guy!"
"I do not know what you mean by that. I am Satan's son, Nick. See that birthmark, shaped like 666?"
"Some kind of Japanese emoticon? I bet it is something perverted."
"It is the number of the Beast and I am SATAN's SON!"
Nick rolled his eyes. "Potayto, potahto. Do you want to know how we deal with your kind in the world of flying islands?"
"Eh?"
And thus Leon fell from heaven just like his spiritual daddy.
