According to her household bio, Yuki, along with her older sister Candy, recently inherited a quaint, modest home from her dearly departed Grandma Behr. Yuki is a loner who values her time with herself and her game console. A total geek with a passion for video gaming, and talent too, even hacking into systems makes her day, despite the reputation it gives, as the most infamous hacker in Windenburg. However, despite this passion of hers, nothing makes her happier than the success of her sister in her DJ career. Candy inspires Yuki and makes her want to be a better self.
She's a member of the Avant Gardes, suggesting she's really into vintage items and literature, or simply doesn't fit anywhere else due to her infamousness and the lack of gaming clubs in town. Additionally, she's also part of the Knights of the Hedge, the cosplaying club where the members dress in suits of armour, even though it isn't known what her interest in such activity is. It also seems that her identity is unknown between the club, due to the suit. Club members, Gunther Munch and Maaike Haas does not know her and Yuki does not know them
- Even though Wolfgang Munch is also in the Knights of the Hedge, neither of the two have relationships with each other, suggesting that they know of Jacques identity, as the leader, but not each other's.