藤守 由宇

Yuu, Kaname's younger sister, advanced grades to join her brother in the same year and class at school. She's also a member of the Esquire Knight order.

Deeply devoted to her brother, Yuu's world revolves around him. A self-taught genius, she's always managed to grasp complex theories and knowledge without any mentor. Inspired by Kaname's dream of knighthood, she sets her sights on becoming a knight, aiming to support and aid her somewhat reckless brother.

Yuu's demeanor is marked by her politeness and quiet nature, showing respect and good sense in her interactions with others. However, her composure tends to waver around her brother, revealing a more emotional and reactive side. While Yuu can maintain the appearance of a typical sibling relationship in public, she becomes noticeably more affectionate and clingy to Kaname in private.

Yuu enjoys collecting items related to Kaname, reading, and surfing the internet. Her favorites include her brother and extra-strong black coffee, while she strongly dislikes anything occult, finding unscientific phenomena frightening.

"It's just the affection you'd expect between close siblings. When it's just us, there's nothing odd about it."