Sara is Noelle's older sister, possessing the ability to turn invisible. She frequently uses this power, spending significant time unseen, which makes her difficult for others to detect. This literal unseen existence fuels her sense of isolation within the family and her belief that she is "The Un-Favorite" among her siblings. While invisible, she typically remains secluded in her room, avoiding family interactions, though she occasionally visits Yuusuke. Her relationship with visibility changes during a beach trip where she actively asks Yuusuke to see her; tape wrapped around her flies off, resulting in her becoming permanently visible. After this transformation, she integrates more into family life and spends increased time with Yuusuke, sometimes flirting with him.

She develops an early attraction towards Yuusuke. Later, her romantic focus shifts when she meets Mikael, falling in love with him. This affection remains unreciprocated due to Mikael's existing romantic relationship with Raphael and his singular focus on angel-related matters.

Physically, she has rose-colored hair and inherits pointy ears from her mother, a trait shared with some siblings like Gabriel. Periods of extreme dieting trigger noticeable instability in her behavior, showcasing a more volatile aspect of her personality.