Megumi Natsu, known as "Meg" or "Megu," is a middle school classmate and close friend of Chino Kafu and Maya Joga, forming the ChimaMame Squad trio. In middle school, she stands at 145cm, the tallest in her group yet relatively short for her age; a significant growth spurt later brings her to 152cm in high school, the most substantial increase among her peers. Her appearance features long red hair, initially styled in unique tornado-shaped pigtails held by purple bands—she dislikes this hairstyle being called "drills." Inspired by Rize Tedeza in high school, she adopts twin tails instead. Her eyes are red and droopy. By high school, her figure develops noticeably. She wears a standard white and navy sailor uniform for school; at Rabbit House cafe, she borrows Cocoa Hoto’s uniform or dons a salmon pink variant.

Gentle, polite, cheerful, and inherently trusting, Megumi’s nature sometimes leads to naivete as she struggles to detect lies. She deeply admires Cocoa Hoto as an ideal older sister and role model, uniquely addressing her as "Cocoa-chan" while using "-san" for others. Despite her kindness and calm demeanor, she often worries about being "too ordinary" compared to her eccentric friends and seeks new versions of herself through growth. Her mother, a ballet teacher, led her to train in ballet during childhood, though stage fright caused her to quit. She later assists at her mother’s studio and discovers an ability to spin at high speeds without dizziness, sometimes dancing impulsively to ballet music. Unexpectedly, she shows talent in hip-hop dancing and baking but considers herself unskilled with manual tasks.

Her development focuses on overcoming self-perceived ordinariness through challenges. Encouraged by her mother, she applies with Maya to an elite girls' high school attended by Rize and Syaro Kirima. With Chiya Ujimatsu’s academic help and Cocoa’s encouragement, she passes the entrance exam. Upon starting high school, she incorporates the newly available ribbon into her uniform. She takes on part-time work at both Rabbit House and Ama Usa An cafe, reflecting her dedication to new experiences. In special narratives, she exhibits sensitivity to dimensional shifts, occasionally switching places with a "different world" version named Natsue Joga; these experiences send her spirit to a sci-fi Tokyo or distant future, offering glimpses into alternate realities. Her relationships fuel her growth: a longstanding childhood friendship with Maya Joga, a close bond with Chino Kafu, admiration for seniors Rize and Syaro, and a polite, supportive dynamic with Chiya, who aided her exam preparation.