A row of Reimu is lining on platform, giving birth despite their wish. They are forced to keep giving birth by the other clan members.
Their baby are born and fallen into a soft cushion below. The one who return their greeting is the chief Patchouli, who teach them that the whole clan member is their mother. Of course, the newborn babies happily accept the many mothers without ever seeing the face of their own parents.
Meanwhile, during break, Reimu are given bitter grasses that no yukkuri would eat except as emergency food. If they refused, they can go outside.
They are then shaked by the Alice and prepared for next childbirth.
At first, Reimu types are part of the clan. But unlike Marisa and Chen, they can't catch bugs. Unlike Patchouli and Alice, they can't find and identify food. What they can are just singing and taking it easy all day. Because of that, the clan grow unsatisfied of Reimu.
The sentiment exploded when a Reimu forced a Marisa to Refreshed! during winter. No reason, they just want to do it. Just with the excuse that little one is cute, they never regretted any of what they've done. The clan is angered. They want to just kill Reimu, but yukkuri must not kill one another.
That's when the chief Alice remembered something. She used to be a pet and from her owner she heard about the horror of the Factory. There, Reimu type are used as seedbed to give birth to baby yukkuri.
Leader Patchouli has a good understanding about their physical treats. With that, the system is created.
The babies are taken to another room and given the same bitter grass. But with words from leader Patchouli and Alice, the babies believed those grasses to be H-H-H-Happyness! tasted. Reimu types are bad eaters anyway, so they can survive by eating bitter grass.
For the good kids, they are given sweets sweets, which are actually the clan's poop. Yukkuri poop are hardened paste, so there's no problem with eating it other than yukkuri feeling that poops are stinky.
Baby yukkuri never have any of those knowledge or beliefs yet. That's why they can easily be made to belief what they eat is tasty.
Same with their "sweet water". Just like poop, yukkuri's pee are simply excreting excess materials in their body. There's no apparent danger of yukkuri drinking it.
Eating many bitter grass, getting rub rub and sleeping well, the babies are happy and quickly grow into Koyukkuri.
Then came the next indoctrination. The little ones are very easy, but they can be even easier. They can be the chosen one, very special yukkuri who can do "please eat up".
Of course, the koyukkuri only understand half of what Patchouli is teaching them. They understand that they're being praised. They truly want to be able to do "please eat up"
The koyukkuri waited in anticipation of the time when they can become the chosen one. Their body is round and healthy with lots of paste from eating many grasses.
Then the time come. One among the ten Reimu in the food storage are called to the dining room. There, she do the chosen one's greeting and her body split in two. She became food for the clan in winter.
This is a loophole to the rule. Yukkuri must not kill other yukkuri, but "please eat up" is an exception. Of course, a yukkuri only do this in dire situation, but these babies has been indoctrinated since they're born to think of "please eat up" as a great honour for the "chosen one".
The grasses grow around the clan's nest, and they can't even finish harvesting those. Reimu type can convert it into paste and delicious babies.
Normally, yukkuri has to be hurt to make them sweeter, but the clan can't use that method. Instead, they indoctrinated the baby and give them a lot of food, making them sweeter through feeling of satisfaction.
The system is proceeding to the next stage now. The babies will be indoctrinated so they "want to give birth to the chosen one".
Reimu who can't give birth anymore is then switched into sperm paste donor, ensuring the children born are Reimu type.
Sometimes, non-Reimu type baby will be born. It's either the type of their ancestor, or because a clan's yukkuri want to refresh with the seedbed Reimu. Those children are taken into the clan.
Meanwhile, the clan is evolving by breeding between the yukkuri with better qualities, excluding the Reimu who now has their part in supporting the clan.
Illustration by: Petshop-aki