Mafuyu is a second-year student at Miyamasuzaka Girls Academy. She's the lyricist of the underground music circle 25-ji, Nightcord de. going by the alias "Yuki". She is an honor student and the only one in her group who regularly attends school. She constantly receives good grades and is a member of the archery club along with the student council. She is said to excel in both academics and sports, hence people often put high hopes for her to excel in everything she does. However, not all is what it seems.

Mafuyu is admired for her smarts, athleticism, and the humble sincerity she shows that keeps any praise for these talents out of her own mouth. She is known to be kind, generous, and considerate, her words always polite and her voice soft and warm. She is difficult, arguably impossible, to anger, for any hesitation she shows that might betray disagreement or displeasure is immediately covered with a gentle smile. She is someone whom others are not afraid to rely on, and someone whom others often put high hopes on, knowing that she has met expectations before and will continue to do so.

To everyone else, Mafuyu is a “good girl.” However, to herself and behind the mask, she is emotionless and apathetic: abandoned by her true self a long time ago, and desperately searching to find it once again. Mafuyu’s “true personality” is considerably more cold and blunt. Her voice is dull and her face is flat, both holding no feeling for she has none to show. She speaks few words, and the words she does speak tend to be no more than what is needed. While she is not pleasant or “good,” she is honest. It’s only within her cold honesty are her true feelings, her true self, given the slightest chance to show themselves, and the other members of 25-ji, Nightcord de. recognize this in their willingness to offer a space where she can be “rehabilitated.”

Mafuyu has a mid range voice, it has an elegant feel but Mafuyu has a high proper voice at times and a lower blunt voice at times