Painting with the Dragon. Book 1. Girls, Boy, Mouse Wedding and Dragon

Excerpts from the book:
As soon as Ōi left the house on the street, she immediately heard a joyful girl’s voice:
“Ōi! Come play with us!”
Turning around, the girl saw her friends: the daughter of a merchant, Satsuki, a very pretty person who would clearly become a rare beauty in the future, and the son of an artisan, Shotaro, a short, strong boy with short-cropped hair. The children got along well and often played ball together, hide and seek, pretended to be ninjas and much more.
And now, Satsuki said:
“Ōi, we're playing hide and seek, come join us!”
“With pleasure! Who is it?” the girl was happy.
“Shotaro!” Satsuki exclaimed in response.
“What? It's not fair! I just did this!” the boy was indignant.
But the girls just laughed and answered in unison:
“It, it! Count to one hundred and we'll hide!”
And they ran away. Shotaro sighed sadly, but honestly closed his eyes and began to honestly count to one hundred.
“One, two...” the boyish voice filled the street.
Meanwhile, the girls diligently hid. Satsuki decided to simply hide behind a large barrel standing near one of the houses. Ōi hesitated for a moment, but then a wonderful thought, in her opinion, came to her. And the girl ran into the gap between the houses, believing that it was there that she could hide well.
Ōi ran and ran, but the gap did not end. Suddenly, the girl began to notice strange things. She saw around her a lot of mice that had come from nowhere. Everything would be fine, except these mice were dressed up in a variety of kimonos and... spoke with human voices!
“Human, human! There’s a human here!” the mice squeaked.
“Where is the human girl here from?” other mice squeaked.
Ōi didn't immediately understand where the voices were coming from. She stopped and looked around. But when she realized the source of the voices, she felt an unpleasant chill grip her and her body covered in cold sweat.
“What's going on here? Amaterasu, help me!” the girl prayed to the sun goddess.
Suddenly, one of the mice, a very respectable one, stopped, turned around and said to Ōi:
“It’s not often that humans come here to visit us, but since you’ve already come, you have nothing to be afraid of. We don't hurt humans. Judge for yourself: you are so big, and we are so small! Why should we hurt you if you can crush us?”
The girl looked at the mouse in disbelief. She was not afraid of mice themselves. But there are so many of them here! What if they all attack her at once? But other mice also spoke:
“Yes, yes, human girl, don't hurt us! And we won’t touch you, because you’re so big! And then you can stay for the wedding!”
“For a wedding? What wedding?” the girl widened her eyes and was involuntarily overcome with curiosity.
“Oh, let me tell you everything in order!” said the first mouse to speak to Ōi.
And then the mouse began the story...