Quitterie Raffaëlli serves as Group B-5's medical specialist, a role mandated by her mother Olive for undisclosed purposes. She possesses tan skin, violet eyes, and long blonde hair typically secured in pigtails with round pink clips, accented by a purple hairband featuring a yellow star. Her attire consists of a white, pink, and black crust suit highlighted with purple and green.

Initially cold and arrogant as a defense against her mother's emotional neglect, Quitterie asserts superiority and distrusts those outside her inner circle. She maintains a strained yet protective relationship with her younger sister Funicia, scolding her for mocking others. Later revelations confirm both are clones of Olive rather than biological sisters.

During the space voyage, Quitterie evolves from dismissing friendships—claiming she joined only for academic credit—to forming bonds through shared hardships. Aries Spring’s persistent kindness pierces her emotional barriers. Her relationship with childhood friend Zack Walker shifts from one-sided affection to mutual love after her direct confession on Icriss, leading to their engagement and marriage.

Charce Lacroix later exposes that Quitterie and Funicia were cloned as potential organ donors in Olive’s conspiracy, severing Quitterie’s hope for maternal love. She redefines family through crew bonds. Her medical expertise—once an imposed burden—becomes critical for survival, treating critical injuries during crises. Interactions like her unease with Charce’s fascination with alien creatures during missions further shape her growth.

By journey’s end, Quitterie abandons seeking Olive’s approval, embracing the crew as her true family. Her arc completes through emotional openness and commitment to Zack.