The Secret Country is the 15th Chapter of Tsubasa: Reservoir Chronicle.
The voice belongs to a young girl: Chu'nyan.
She and the attacker, the son of the Ryanban, have had run-ins before. She thinks the son is stupid, and tells him directly. He doesn't take kindly to her insults, reminding her that his father wields a lot of power in the town. He stomps off the marketplace, promising to claim retribution for her insolence.
The travelers realize that they've created trouble for the vendors by their arrival. They begin to assist the townspeople by putting back the goods and the boxes to their rightful places. A couple of the ladies lament these disturbances caused by the Ryanban and his son; they yearn for the day when the amenosa would arrive.
Chu'nyan was helping clean up, when she looks up and notices Syaoran and his weird clothes. She realizes something and then grabs Sakura's hand and runs off. The others join in and leave the marketplace in a rush.
In Chu'nyan's home, she carefully looks at these strangers. She seems to be waiting for them to say something. They look at her with blank stares, unaware of what she's expecting from them. She sighs, saying that "children like them couldn't possibly be the amenosa".
The amenosa, she explains, are agents from the government who travel from town to town, correcting the evils from corrupt Ryanban. Since her town has been suffering from the rule of an oppressive Ryanban, she has been awaiting the arrival of the amenosa to exact justice on the lord. Furthermore, Chu'nyan has a personal grudge against the ruling Ryanban, as he was the man who took her mother.
Outside, a loud wind rumbles. Chu'nyan warns them from going outside. In the span of a second, a tornado builds up, destroying a good portion of Chu'nyan's house. Fai says that the tornado was not caused naturally -- Chu'nyan blames the Ryanban. It is all his doing!
In the fortress, a man stares at a shimmering crystal sphere. The Ryanban's son walks up to his father and compliments him on his use of the magic. Neither are sure if Syaoran and the others are indeed the amenosa -- but it doesn't matter. For within the sphere is Sakura's feather and as long as they have the feather, they can't be defeated.