Lee Somang, known as Nozomi Yumehara in the original Japanese version, is the main protagonist of the Yes! Precure 5 duology. She is a second-year student at L'École des Cinq Lumières Academy. At the start of the series, she is portrayed as an airheaded and somewhat clumsy girl who does not know what she wants to do with her life. She is easily distracted, especially by food, and often acts on impulse rather than careful thought. Despite these traits, she possesses a deeply optimistic and kind-hearted nature, always ready to help others without hesitation. Her defining catchphrase is "Decided!" which she exclaims when she makes up her mind about something, often without full consensus from those around her.

Her life changes when she discovers a magical book called the Dream Collet in her school's library and meets Coco, a fairy prince from the Palmier Kingdom. Coco explains that his kingdom has been destroyed by the Nightmare organization, and his friend Natts is trapped within the Collet. To restore Palmier, they must find fifty-five magical items called Pinkies to complete the Dream Collet and grant a wish. Touched by Coco's plight and determined to help, Somang's kind heart and resolve demonstrate that she possesses the qualities of a Pretty Cure. A pink butterfly grants her a Pinky Catch, allowing her to transform into Cure Dream, the leader of the team.

As Cure Dream, she embodies hope and the power of dreams. She introduces herself as the "great power of hope, Cure Dream." In her transformed state, she becomes noticeably more serious and focused, gaining strength and courage that she sometimes lacks in her daily life. Her costume is pink, and her hair grows longer with large ring-shaped pigtails held by yellow swallowtail butterfly-shaped clips. She also gains pink butterfly earrings.

Somang's primary motivation is to help Coco fulfill his dream of restoring the Palmier Kingdom, and in doing so, she discovers her own dream and purpose. She initially lacks direction but finds meaning in her role as a Pretty Cure and as a leader. She naturally emerges as the de facto leader of the Pretty Cure 5 team, uniting the other four members through her optimism and determination, even though she often humbly downplays her own role.

Her key relationships are central to her development. She forms a close bond with Coco and develops a crush on him in his human form, a feeling that grows throughout the series and creates a light romantic tension alongside Milk, who also has feelings for Coco. Somang also builds strong friendships with her teammates: Rin Natsuki, Urara Kasugano, Komachi Akimoto, and Karen Minazuki. Though they are very different from her and from each other, she learns to become their friend and their leader, growing through each challenge they face together.

Throughout the series, Somang undergoes significant personal growth. She begins as a carefree student without clear ambitions and evolves into a confident and reliable leader who values friendship, courage, and determination. Her experiences fighting against Nightmare and later against the Eternal organization in the sequel season Yes! Precure 5 GoGo! teach her that dreams can become reality when one has faith in oneself and in others. In the sequel season, she and her team regain their powers to protect the Cure Rose Garden, and she receives a power-up form called Shining Dream in the second movie.

As Cure Dream, her notable abilities include transforming using the Pinky Catch, performing team attacks such as the Five Explosion alongside her fellow Cures, and later, in the sequel, using the upgraded Floral Explosion and Rainbow Rose Explosion techniques. Her powers are associated with butterflies, dreams, and hope, reflecting her role as the leader who inspires her team to keep moving forward.