Aya Maruyama leads Pastel*Palettes as vocalist after three years of intensive training, achieving a pivotal step toward becoming an idol she genuinely admires. Outwardly cheerful and energetic, she conceals profound insecurities and a craving for validation, often manifesting as stage nerves that trigger tears and impair improvisation or MC segments. She obsessively checks online feedback and avoids disguises in public to remain visible.

Academically challenged, Aya struggles most with math and even finds aspects of Japanese occasionally foreign. Beyond music, she diligently maintains a personal online journal and perfects selfie techniques with original "idol poses," habitually carrying a selfie stick despite light teasing from peers like Eve.

She adores spring but actively detests horror. After positive reactions to a magic act at the We're All Here! New Year's Party!! event, she secretly practices magic tricks. Aya shares a close bond with her younger sibling and matches certain bandmates in height.

Within group dynamics, she mentors Kasumi from Poppin'Party as a senpai, constantly anxious about fulfilling this role commendably despite her vulnerabilities. Her participation extends to the BanG Dream! FILM LIVE 2nd Stage as a main character representing Pastel*Palettes alongside other band leads.