Yuki is a young woman with a personality that can be considered an acquired taste. Abrasive and hyperactive, she is competitive and can come off as arrogant and rude at times. While she can be hard to handle, Yuki is very caring, can be overprotective, and will always put Pokémon and those she cares for before herself. Yuki was once part of an organization that not only stole Pokémon but also concocted ways to use them to take over various cities and regions. While Yuki only joined as a way to take care of herself and the Pokémon in her company, she still feels guilty over her short time with them and works hard to atone for her wrongdoings. As a young child, she was experimented on by the scientists of Team Rocket, resulting in her ability to link her psyche with Pokémon near her and use their moves. However, because of this, she often gets sick due to those experiments weakening her immune system.

Yuki enjoys spending time with N, her friends (Tasha, Jet, Troy, and Yuri), and her Pokémon. She has a deep love for historical architectures and the history of various towns and cities. She loves watching Pokémon contests. She occasionally competes in them. However, it's obvious how nervous she is when competing which results in her painful losing streak. She adores volunteering at Pokémon Daycares and helping Nurse Joy at the Pokémon Center in Lilycove. She is terrified of lakes and oceans, though she feels the most tranquil riding on her Charizard's back over large bodies of water. Though Yuki cherishes all of her Pokémon, her number one partner will always be her Mightyena. Whenever she is feeling down, he likes to wear her hat to make her laugh.