Masao Ichinokura, a 29-year-old aspiring singer, lives alongside the Yamada sisters in the same apartment complex. Sustaining himself through part-time work, he chases his musical dreams with occasional aid from devoted female fans who provide meals. His evolving relationship with the younger sister, Asu, becomes a cornerstone of his personal growth. When Asu grapples with a school singing assessment, hindered by her belief in her own tone-deafness, she turns to Masao for help. He mentors her in vocal techniques, empowering her to conquer the challenge. Simultaneously, her relentless optimism and drive rekindle his dedication to music amid professional setbacks, solidifying his refusal to surrender his ambitions.

Masao’s history of financial strain and the struggle to reconcile artistic pursuits with survival needs ground his character. His arc exemplifies mutual mentorship, where guiding Asu fuels his own perseverance. Their dynamic illustrates reciprocal empowerment, casting Masao as both a teacher shaped by the sisters' resilience and a beneficiary of their enduring spirit.