"Ogre" was not actually the right name.
Because ogres did not only eat humans; they ate every kind of living creature. It was simply that intelligent humans benefited them the most, allowing them to transform from beasts into intelligent life forms.
So once an ogre had tasted an intelligent life form, there was no going back.
When Jayne was first born, he had merely been a small black ball in a river. There were countless little balls like him, all instinctively foraging for food.
Some small balls ate tadpoles and transformed into tadpoles for the first time. Some ate little fish and became little fish.
Jayne had been quite lucky. The first time he foraged for food, he ate a dying electric eel. With the eel's abilities, he developed much faster than his other companions.
After about a week, his body had become half crocodile and half giant snake.
He left the river where he had been born and wandered through the forest in search of food. Wolves, tigers, cattle, deer, venomous snakes, eagles—everything was food to him. His form changed constantly, gradually turning him into a monster pieced together from various creatures: the body of a wild bull, the head of a tiger, the tail of a crocodile, and the wings of an eagle.
The transformations were completely random, without any planning whatsoever.
And so, he lived year after year until one day, he encountered a human.
The human was in a terribly bedraggled state, covered in wounds with a gray, dejected expression. He even held a hemp rope in his hand, as though he were preparing to hang himself.
Of course, Jayne did not understand such things at the time. He merely approached on instinct and looked at the creature before him, one he had never eaten before.