Tsumugi Yuuki can be described as shy and determined. She is an electric pianist in the same band as Karasuma. She is often seen with Mai or with her band. Although she is shy, she is by no means a pushover. During the survival game, she showed how she was a force to be reckoned with. She is also a member of the Astronomy Club.
In the Manga, Yuuki makes her first appearance in chapter 22 “Duel," cheering on the Pool Battle.
The trading cards identify Yuuki's signature skill as 'Astronomical Observation' (stating that she has the power of '2 Dwarf Stars'). Yuuki has been in the astronomy club since junior high school, and participated in a camping to the mountain in the Nagano prefecture in order to see shooting stars. She still yearns to continue her studies in Cosmological Physics, and if possible go into space. Consequently, she strongly admires the famous astrophysicist, Stephen Hawking, who is the Lucasian Professor of Mathematics at Cambridge University.
Athletic Skills Edit
Yuuki rides her bike to school every day, ensuring she remains in good shape. One can expect her to have strong legs, as shown by her skills at swift motion during the Survival Game. She is a member of the girls basketball team. Acting as a reserve player, she was a starter in the match against The Outlaws replacing the absent team star, Satsuki Tawaraya.
Combat Skills Edit
Yuuki has strong stealth skills and is more than a match for Mikoto Suo with ranged weapons, favoring the sling shot. She has shown no sign of hand-to-hand combat skills, but can move very fast when sufficiently motivated, while remaining concealed.
The Trading Cards identify her 'finishing blow' as 'Finding Planets', which probably does not bode well for her luck in a fight sans sling-shot.
Alternate Yuuki Identities Edit
During the play at the Cultural Festival, Yuuki took on the role of some sort of fairy who posed a riddle to the gang of Princes. Sadly, Tenma Tsukamoto answered incorrectly and as a result, the princes were out of luck.
Yuuki holds a not clearly defined role as assistant to her friend Mai Otsuka, the Chairman of the Class Committee. Whatever her exact job, this led her to assist Mai in sifting through the scripts for the class play.
Meganekko (Spectacles Girl) Edit
The trading cards identify her spectacles as her weakness; Yuuki has very poor vision and cannot even make out a sunset without her glasses. Interestingly, this very trait makes her popular among fans of girls with the glasses look.
Yuuki appears to have a crush on Hanai. Hanai gave her a ride home on her bike after Yoshidayama accidentally broke her glasses. He admired her ability to make it up a steep hill and offered to watch the beautiful scenery with her. Although her glasses were broken, he positioned a broken piece of lens to allow her to see the beautiful rainbow. During the Survival Game, she was willing to get "killed" so that he could win the game when he confronted her, and while the class was cleaning up following the cultural festival, she seemed quite pleased when Hanai complimented her on the onigiri she had prepared. She seems to find Hanai uncool or just said that to deceive the other members of the Astronomy Club.
In b35, Yuuki was a bit depressed after seeing Hanai and Mikoto shopping.
Chapters #233 and #234 both deal with Yuuki's desire to confess her feelings for Hanai.
It seems that Yuuki is a bit jealous of Hanai's and Mikoto's close friendship. During the survival game, Yuuki was willing to take down Mikoto without hesitation, but once Hanai showed up, she was willing to sacrifice herself for him.
Yuuki is Mai's chief flunky in student government, assisting her with such duties as picking the class play. It's unclear whether Yuuki holds an official position in student government or whether she simply assists Mai out of friendship.
Sagano and Yuuki tend to be partners in gossip-crime, trying to get to the bottom of everyone's romantic lives, such as their tag-team assault on Eri Sawachika's romantic secrets at the bathhouse.