Spring is coming
In a mountain separated from human village, there is yukkuri clan led by Patchouli.
Before winter arrived, Patchouli is the last yukkuri still not yet entering her nest to hide until winter pass. She's making sure every member of her clan is ready.
Luckily, there's enough food and there's no scum here. Patchouli also hoped there's no idiot who make little ones during the winter. If everything goes well, they will party with the sakura tree that is their clan's symbol together. Beautiful sakura and delicious fallen petals, truly something to expect.
The cold north wind tells Patchouli that winter has arrived, so she hurriedly enter her own nest hole.
After some while, a pair of Reimu and Marisa is awaken in their nest. They felt warm air from outside so spring must have came. Marisa suggest they wait until the morning before going out.
There's still a lot of food left. Reimu is proud of her ability to ration their food.
Outside, the yukkuri gathered around the blooming sakura tree, admiring the beauty and awaits for the feast of petals.
Patchouli told them it will take a few more days before the petals fall to the ground and can be eaten, so today, everyone will go hunting as usual.
But there's no insect. Water is still locked under layer of ice and weather is still cold. In place under shades, snow still sits like in winter.
In reality, this is the end of January. 10 days ago there's a big forest fire. The fire is intense but luckily the fire never reached this part of the forest. The hot air though, warmed this area.
It's not strange for the yukkuri to be fooled. Even the sakura tree thought spring has arrived and blooms early. Clan members believed Patchouli's words that sakura signed the coming of spring, so they never thought of returning to their nest.
If they do resume their hiding, the yukkuri would have survived. In hiding, their low activity made them consume less. But thinking it's spring made them move actively outside. The stress also caused them to eat more and thus, the clan died of starvation.