In the corner of a garden near the sky, there is a bird cage covered with cloth.
A few days ago, Mary who is full of curiosity sneaked into the forbidden entrance and found the talking monster Colin trapped in the cage.Colin said that he did not remember why he was caged.

Mary who has lost the memory of her youth was raised by a magician.
In a large house hidden in the cloud all year round, there was no one that Mary could talk to before she found Colin. She came to see the monster Colin again while the magician was away and she does not realize that the magician felt something was wrong and was hurrying back home.