Kamakurako (かまくら子, "Kamakura child"), is a character in Madotsuki's dream world. She's in a deep sleep in an igloo to the southeast of the entrance to the Snow World.
She has brown hair, wears a gray shirt and black bottoms and closely resembles a younger version of Madotsuki with her hair let down. Although it seems that nothing can break Kamakurako out of her deep sleep (besides killing her), she seems to react when Madotsuki meows when using the cat effect with a small tremble. Whether she is shaking from fear or from the cold is up to fan speculation.
Similar to all other NPCs in the game, she has no actual name in the game, but was called "Kamakura child" since the igloos are highly resemble and is probably a reference to the Kamakura festivals of northern Japan where child play house in little snow huts. (References: [1] [2] [3])
Fan Speculation
Little can be said about Kamakurako due to the limited action she provides. It could be possible that she has a fear of cats considering their sound is the only thing she react to.
It is also possible that she is a younger version of Madotsuki when compared to Madotsuki when she's sleeping with long hair (Kamakurako's hair is slightly shorter than Madotsuki's).