| SPOILER WARNING!!
- "In the extreme cases, when practitioners of black magic in the west wanted their wishes granted, they'd sacrifice a woman! Woo! It's so scary!"
|Full Name||Keisuke Yuki
|Hair Color||Light Brown|
|Known Relatives||Unnamed Mother|
Miaka Yuki (Sister)
Taka Sukunami (Brother in-law)
|Occupation||University Student, studying Chinese Philosophy (Original Series)|
|Created by||Yuu Watase|
|Voiced by||Shinchirou Miki (Anime)|
Derek Stephen Prince (English)
Keisuke Yuuki (夕城 圭介 Yūki Keisuke), is Miaka Yuki's older brother. He conducts research surrounding the history of The Universe of the Four Gods while he reads along as his sister's adventure inside the book unfolds.
Keisuke is depicted as a typical twenty year-old in school, dressing in mostly hoodies, t-shirts, and the occasional turtleneck and casual button up with jeans. On occasions, he dresses up his outfits with a nice jacket or blazer. On the taller side, he has a slim build and is shown to have light brown hair and dark grey/black eyes.
Keisuke is selfless, brave, and surprisingly grounded for being a humorous and easy-going college student.
His genuine attitude and comedic jokes make him well-liked and respected by others. Keisuke wears his emotions on his sleeve as he openly cries over character deaths inside the book and in reality. He is also shown to get obsessive and fan-like, especially when Tamahome arrives in the real-world and he begins to hero-worship him.
His dynamic Miaka is a typical sibling one (teasing, sarcasm, etc.). But, from the beginning, there is an air of sympathy around Keisuke‘s interactions with Miaka. He finds himself fulfilling the role of his absent father. When their mother berates his sister for her low test scores, an understanding Keisuke assures Miaka that “I wouldn’t tell you [your scores were bad] even if I knew.”
Keisuke is not quick to believe Miaka's tale about the Universe of the Four Gods, however, he still cautions her even in his doubt. It is not until he watches her disappear into the book that he is convinced of its power.
He is very aware of his limits and abilities regarding the protection of Miaka. On top of helping Yui search for her when she enters the book alone (in the manga), he uses his mother’s trust in him to come up with an excuse for his sister’s disappearance. When he discovers the book, instead of attempting to blindly trail Miaka, he understands that his strength lies in his intellect and he defers to researching the history of the book. Therefore, his role in the story is very much like a detective as he teams up with his best friend, Kajiwara Tetsuya.
Relationship with Tetsuya
Keisuke and Tetsuya are shown to be best friends. Both humorous in nature, Tetsuya is the cool-headed and skeptical Watson to Keisuke’s inquisitive and dramatic Holmes. Keisuke even has a "spot" in Tetsuya's car and they both share a mutual love of beer.
- In the Filipino Dub, he was renamed as Kenny.
- Throughout the series, he goes to university and majors in Chinese Philosophy.
- In the manga, Keisuke owns a motorcycle.