She sends the travelers the White Mokona (Soel), which acts as both the party's dimension transporter and interpreter additionally it serves as an intercom between Yūko and the party, it also helps monitor the places where they are grant requests and exchange payments, such as the dress Sakura made for her and the Chocolate Lava cake they had in Outo country. Yūko is apparently one of the few people with the power to send people to multiple worlds as the Witch of Dimensions, she informs Syaoran and company what awaits in this quest of collecting feathers Sakura's feathers, and maintains her rule of exchanging something important from each character, a price to pay for their wish of travelling dimensions. In the story, her role is not a leading one but not less important, in relation to the plot that develops between the different 'worlds' that the characters visit. She has also mentioned being acquainted with Sumeragi Subaru and his sister and has been aware of the Sakura Kinomoto of Cardcaptor Sakura for some time, claiming that one day she wants to meet both Sakura Kinomoto and Syaoran Li.

But it rather seems that they were preparing for the arrivals of the Tsubasa group and Watanuki. She has in her possession a replica of Sakura Kinomoto's first Clow staff, as well as the real Star Staff and has been known to complain mightily about her annoyance with Clow Reed's personality. They were created for the exact time when Syaoran and the others would come to her shop asking for her help. Soel has a red gem (multiplies magic) and Larg has a blue gem (seal magic).

In the novel Soel to Larg: Mokona=Modoki no bouken, released in Japan about the origins of the two Mokonas, it was mentioned that Clow Reed and herself met the original Mokona of Cephiro (Magic Knight Rayearth) thus making it the model for building the two smaller Mokonas (Soel and Larg). The price is always equivalent to the importance of the wish, no more, no less. Yūko is the owner of a mysterious shop in Tokyo and a dealer in wishes as she will grant the sincere wish of anyone who is willing to make an appropriate sacrifice in return.

2 Storyline in Tsubasa Reservoir Chronicle.

Taito kuragane anime character database