Machi Kuragi is the treasurer of the student council, with Kimi Toudou and Naohito Sakuragi as secretaries, Yuki Sohma the president, and Kakeru Manabe as the vice-president. She is Kakeru’s paternal half-sister. Kakeru was born first, to their father’s mistress. Machi is younger—she was born to their father’s legal wife, which led to their mothers fighting over which child would be the heir to the family fortune.
Machi's mother always forced her to be perfect; she never showed Machi any maternal warmth or love and never praised her for her hard work. As a result, Machi came to regard herself as a “thing” that was not needed in this world. She developed feelings of intense unworthiness in herself and a hatred for things that were “perfect”—like untouched snow, organized closets and unblemished chalk. She walked circles in snow and would go on rampages at school, destroying clean, organized spaces because of her hatred and fear of “perfect” things.
Kakeru dropped out of the race for the family fortune in middle school, thus freeing his eccentric, outgoing personality. Machi's mother had a son while Machi was in middle school, and it was decided that he would be the heir to the family fortune.
One day, Machi saw her younger brother sleeping. She thought he might be cold and covered him with a blanket. However, her mother came in and automatically decided that Machi was trying to kill her younger brother without even clarifying with Machi first. She was then banned from the house and forced to live in an apartment by herself.
She is the treasurer of the Kaibaea High School Student Council, and she becomes closer to her fellow officers, half-brother and eventually Yuki Sohma, the President. After different events where Machi and Yuki begin to recognize their similarities and truths about each other, they begin to grow closer. Machi's life starts to grow brighter and more enjoyable.
When Yuki hears rumors that Machi tried to kill her younger brother, Kakeru takes Yuki to go visit Machi. She confesses the true story to Yuki, and they nearly kiss. However, Kakeru's phone rings and they are interrupted.
Everyone thinks Yuki is a prince, but Machi sees through his act and sees that he is very lonely. When Yuki hears that, he is surprised that she sees the truth; over time they share their experiences and grow closer.
At the end of the series, Yuki called Machi and asked her to meet him at a certain spot. He was planning on telling her about the curse, but then his curse broke unexpectedly. Instead, he told Machi that he loved her. Machi asked him if she could call him by his first name, to which Yuki consented and they begin their relationship.
In the last part of the series, Yuki gave Machi the key to the apartment he will be staying in while he attends a university.
In “Fruits Basket Another” it is revealed that Machi and Yuki married and had a son, Mutsuki Sohma. Mutsuki is close to and loved by both his parents. He is also close to his cousin Michi Manabe, the daughter of Kakeru and Komaki Manabe.
Mutsuki is also close to many of the Sohma relatives of his generation, like Hajime Sohma, Riku Sohma, Sora Sohma, Kine Sohma, Hibika Sohma, Chizuru Sohma, Shiki Sohma and Mina Sohma.