[Ghost Stories of the Seventh Night] The Borer

"Wild bugs follow the law of survival of the fittest. They live and live, and when they encounter a powerful outsider like a human, they run because they know they'll be killed. But what about bugs raised by people and deliberately thrown into a fight? They have no choice but to kill until only one is left, so they can be safe in the jar. Then the bug keeper opens the jar and fishes out the bug that has eaten all the corpses. He tames it and trains it. Though it's become many times stronger, it can't live freely anymore. It can only become dependent again on the one who harmed it, with its life or death decided by the bug keeper's whim. In the end, it has less chance of survival than before it went into the jar and grew stronger. If it understands human nature too well, and the bug keeper is even crazier, he'll have it chirping things like 'Dad' and 'Mom'... Ugh! How dull, right? Bugs hatch from eggshells. They see no blood or flesh when they're born, so naturally they have no reason to call anyone Mom or Dad. If they did, they might just become their parents' food. When a grown adult insists on being a bug's parent, should we say they have too much kindness in their heart, or that they've plainly written the thought 'That's food waiting to be used, waiting to be eaten when the time comes' all over their face?"

Theme: Whatever the animal, once it has been tamed by humans, it becomes their possession and is expected to imitate human nature. Calling themselves its "parents" is simply the most common way of standardizing how people refer to animals that have been tamed.