Momo Sohma is Momiji Souma's younger sister. Unlike her older brother, she is not cursed with a vengeful spirit of the Zodiac. After Momiji was erased from his mother's memory, Momiji's mother and father had a daughter, Momo. Not wanting to destroy his new happiness, Momiji's father forbids Momiji from interacting with Momo. Ironically, Momo is interested in knowing Momiji and attempts to find ways to discover more about him. She sees a great resemblance between Momiji and their mother (who denies it). When Momo catches Tooru attempting to sneak into the Souma complex, Momo shows Tohru a secret way in. She asks Tooru to ask Momiji if he would like to be her older brother. Momo had started to learn how to play the violin, which meant that in order to maintain the separation, their father asked Momiji to quit (otherwise they would have had the same teacher). It later turns out that she saw Momiji playing and was hoping that if she learned how, they would be able to play together. When Momiji hears from Tooru that Momo wants him to be her older brother, he begins crying tears of joy. Momo is referred to as "cute" by her elder brother, and almost always stays near her mother, "like a baby chick."