Duenote Ayase, known as Megumi Ayase in the original Japanese, reigns as Parthenon Productions' top idol prior to Creamy Mami's arrival. Her established singing career faces upheaval with the sudden emergence of this magical rival, sparking significant professional jealousy. This competitive dynamic shapes her initial character arc, as she perceives Creamy Mami as a direct threat to her agency status.

Ayase exhibits a spoiled, self-centered, and temperamental personality, frequently responding to challenges or slights with dramatic outbursts. She directs this behavior towards agency staff, especially manager Hayato Kidokoro, subjecting him to verbal abuse and physical comedy like slapping or throwing objects in frustration. Her motivation intensifies due to implied romantic feelings for agency president Shingo Tachibana, whose professional focus shifts towards Creamy Mami, deepening Ayase's resentment.

The spin-off manga *Magical Angel Creamy Mami and the Spoiled Princess* delves deeper into her background. It reveals her longstanding dedication to her career, starkly contrasting Creamy Mami's seemingly effortless magical rise. Ayase's initial hostility stems from viewing Mami's success as unearned, fueling her determination to reclaim her position through rigorous training and strategic moves. This rivalry evolves beyond jealousy; Ayase gradually acknowledges the complexity of competing against supernatural abilities, prompting introspection about her own ambitions. The manga charts her journey toward nuanced maturity, channeling competitive drive into genuine artistic growth instead of solely opposing Mami.

While the original anime primarily frames her as a comedic antagonist, later episodes hint at minor softening during collaborative or high-pressure scenarios. However, the spin-off manga provides the most substantive development, concluding her arc with a balanced perspective. This retains her ambitious spirit while diminishing earlier pettiness, portraying her transition from insecurity-driven rivalry toward resilient, self-aware professionalism.