Yuki Kaida (Japanese)
Yumiko has shoulder-length light brown hair that has bangs swept to the left side, dark brown eyes, red lips and she is somewhat taller than her younger brothers.
Yumiko is the type of sister who really shows on how she cares for her younger brothers. Other sources found out that she sometimes stops the fight of her younger brothers. Her pleasing attitude towards her brothers is very good. She's very supportive when it comes to the matches of her brothers.
Yumiko is known by some students of Seigaku and especially at St. Rudolph because of her good looking face, great personality and because of Hajime Mizuki. She is shown when she offered Shūsuke Fuji a ride before the delayed championship against Rikkai. Also, she came when Shusuke was having a match with Akaya Kirihara and she described on how competitive and protective Shusuke is.
- The name Yumiko means "reason, case, cause" (由) (yu), "beautiful" (美) (mi) and "child" (子) (ko).
- Yumiko's surname Fuji means "not" (不) (fu) and "two" (二) (ji).
- In the videogame "Gakuensai no Oujisama", the main character finds a "Fortune Telling" book written by Yumiko.