|Base of Operations||Karakura Town, Japan, Human World|
|Relatives||Unnamed mother |
Miyuki's appearance is that of a young girl with short, brown shoulder-length hair, gray eyes and a perpetual blush on her cheeks. 
Miyuki, whose parents split up, doesn't have any friends and spends most of the day alone with her only companion, a stuffed doll. The doll, named Shintarō after the dog she used to have, was so important to Miyuki that she risked her own life to save the doll after it accidently fell into a river. 
Miyuki used to live with her family and her dog Shintarō in a big house. After her parents divorced she went to live with her mother in an apartment complex and, since dogs were not allowed, her mother bought her a stuffed animal which they named Shintarō as well. Some time after that the real Shintarō was run over by a car. 
While walking by a bridge, Miyuki accidentally drops her doll Shintarō into a river and falls in while she tries to retrive it. Shintarō, now housing Kon thanks to Rangiku Matsumoto, grabs and pulls Miyuki ashore. After waking up, a policeman asks her if she is all right, to which she replies that Shintarō saved her. Back home, Miyuki proceeds to dry off Shintarō and, as she sticks a hair drier in its mouth, she discovers that her doll can now move. Kon, inside Shintarō's body, asks her if they are all alone and she tells him that her mom works till late and her father was forced to leave them as he was a good-for-nothing.
Miyuki asks Kon to play with her and he tells her that it is a nice day outside and she should play with her friends. Miyuki then tells Kon that she doesn't like to go outside and she doesn't have any friends either, to which Kon asks why was she outside before. Miyuki tells Kon that she was trying to visit the house she lived at when her parents were still together. Kon decides to take her there. As the two arrive at the house, they notice a knocked-over bottle with a flower. Miyuki tells Kon it is where the real Shintarō had died. Just then, Kon feels the presence of a Hollow and takes Miyuki to a safer place. The two are chased by a Hollow which Miyuki cannot see clearly. Kon takes Miyuki to hide from the two-headed dog Hollow. Miyuki watches Kon inside Shintarō body attempting to fight the Hollow to no avail while she tries to escape. As the Hollow moves in to attack her, she cries for Shintarō's help and one of the heads of the Hollow begins to attack the other.
With the Hollow presence gone, Miyuki rushes over to Kon who tells her that she is lucky and that the real Shintarō saved her. Kon then gives her a lesson in tough-love and tells her that she needs to make friends and not rely on him forever, as well as telling her that both the doll and the original Shintarō will always look after her. After the police arrive she is reunited with her mother. Kon, now in his real stuffed animal body, wishes her to do her best.