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Spring is the season where young yukkuri finally leave their parents' nest. In this nest, a pair of Reimu and Marisa is parting with their daughter, a Sanae.
Sanae is a changeling. Originally Reimu and Marisa wants to just crush the baby, but they don't because it would make them uneasy. So they raised Sanae at side of the other siblings.
Of course, baby yukkuri get death flag just by existing. In the end the other common type children died and both parents learn to love their remaining child after managing to pass the winter together.
Now, with no children, Marisa and Reimu begin to make their next little ones. Reimu is so confident in her ability to raise child. They can't even wait until night.
Reimu had five fruits growing from her stalk. Reimu, Marisa, Reimu, one after another.
Seeing the Reimu hanging from end of the stalk is about to be born, Reimu called Marisa. Marisa is out hunting. Even if she only hunt around the nest, it would still take time for her to return back inside.
The first baby Reimu fell to the ground, breaking her feet.
Baby yukkuri are weak, but these fruit stage yukkuri are even more fragile. It's a parent's job to capture lest they die. In case of the child from the end of the stalk, Reimu wouldn't be able to reach the child with her braids, so it's her partner's duty to do so.
Marisa returned just in time for the four children to be born together. This time, they managed to capture the four children and gave them stalk as their first meal.
The eldest baby Reimu has long gone from their memory.
After eating, the children feel sleepy and is going to sleep.
This is when Marisa told the little Marisa that they are going out to hunt. The children of course protested. They are denied of the easyness to sleep and eat.
Now, you might has seen where this is going. Marisa's standard for a child is Sanae. Marisa bring the newborn Sanae out to hunt. Her idea is if she died, it's by an accident; if she survived then there's that.
Sanae survived, and she even captured a bug who is then served to her other siblings.
Marisa thought that her Marisa children should be superior to Sanae, so going to hunt after being born is just normal.
Ignoring the children's protest, Marisa dragged the two Maricha out to hunt. She thought the children are happy and surely this hunt will be bountiful. After all, these are Marisa children, much superior than a Sanae.
Back at home, the Reimyu are also sleepy. One is asleep while the other one only think how noisy those other yukkuri are.
Reimu doesn't want to lose to Marisa. She called the sleepy children to practice singing.
Yes, as soon as Sanae came back home, Reimu trained her singing and told her to clean the house. Now surely Reimu's children, the supreme race, could do better than a Sanae.
Of course the baby Reimyu are not motivated. Instead, one of them saw something shiny in Marisa's storage and put it into her mouth.
That is Reimu's treasured marble. The mother quickly beat her child to death, demanding the marble, which is accidentally swallowed during the beating, to be returned.
In the end, Marisa and Reimu are too tired and told the children to sleep outside as punishment for bad behaviour. They will be given more punishment tomorrow.
That never happened because a Remirya found both children, too tired and unable to sleep because of the cold and darkness. Remirya killed both children.
Marisa and Reimu found both their children died the next morning. But rather than sadness, what's in their mind are question, why could something impossible like this happened.
Needless to say, Marisa and Reimu's children later also ends with the same meaningless death. Both are using Sanae as standard, something no normal type kids could endure.
Meanwhile, Sanae is going to far away land. She always thanked her parents and thought all her suffering is for future happyness.