Nodoka Haramura is a first-year student at Kiyosumi High School in Nagano Prefecture and a protagonist in the manga "Saki". She is also a supporting character in the spin-off manga "Saki: Achiga-hen episode of side-A". She has played online mahjong since a young girl and develops a eventually passion for it. Her father, who works as an attorney, disapproves of Nodoka's interest but does not prohibit it. Because of her mother's work assignment, her family usually moves to a different city every two to three years. She moves to Nara Prefecture prior to her final year in elementary school and soon enters Achiga Girls' Academy for middle school. While in Nara, Nodoka befriends Shizuno Takakamo and briefly joins Achiga's mahjong club. Nodoka's family moves again after one year at Achiga to Nagano, where she enters Takatoobara Middle School and meets Yuuki Kataoka. The two join its mahjong club and meet younger teammates Hiroko Murohashi and Maho Yumeno. Takatoobara enters the prefectural middle school mahjong tournament the following year but does not qualify for the national tournament. However, Nodoka qualifies in the individual tournament and proceeds to win the national championship. She begins receiving much publicity after winning the national title, and the media often exaggerates her skills as a mahjong genius. Her family plans to move again after she completes middle school, but Nodoka wishes to remain in Nagano and enter Kiyosumi High School with Yuuki. Her father reluctantly agrees, and she aims to also win the national high school championship in return. Upon entering Kiyosumi, she meets fellow first-year student Saki Miyanaga is devastated by the fact that Saki possesses skill in mahjong that surpasses her own. Nodoka's initial contempt for Saki eventually disappears, and the two grow closer to each other with the promise of reaching the national high school mahjong team tournament with Yuuki and their senior teammates.
Nodoka's true strength in mahjong lies within her online persona. Using the pseudonym "Nodocchi", her winning record surpasses that of most professional players. Her opponents have observed that she makes makes the most complex decisions within a split second and rarely makes mistakes in her plays, if ever. Although Nodoka does not publicly confirm her online identity, Ryuumonbuchi High School's Touka Ryuumonbuchi is one of the few who believes she and "Nodocchi" are the same person. Contrary to her speed online, Nodoka's gameplay efficiency decreases when playing in live matches. Hisa Takei attributes this to distractions caused by her surroundings. Upon Hisa's recommendation, Nodoka plays her tournament matches with her stuffed penguin Etopen in order to maintain her concentration. Nodoka is pragmatic and refuses to believe in any supernatural factors or superstitions involving mahjong, dismissing them as mere coincidences. She believes strongly that it is skill, not luck, that determines a winner. Her strong belief in logical play often causes her to come into conflict with players who gamble with chances while playing, including Hisa.