"Kirei no Tamago" centers on the life of Tamago, a young woman who struggles with societal expectations and self-worth due to her unconventional appearance. Tamago, whose name translates to "egg," is often ridiculed for her round, egg-shaped face, which contrasts sharply with the beauty standards upheld by those around her. Despite her outward appearance, Tamago possesses a kind heart and a resilient spirit, which she channels into her passion for baking. Her dream is to become a renowned pastry chef, a goal that becomes a driving force in her life.

The narrative unfolds as Tamago enrolls in a prestigious culinary school, where she faces both overt and subtle discrimination from her peers and instructors. Her journey is marked by a series of challenges, including intense competition, self-doubt, and the pressure to conform to societal norms. However, Tamago's determination and creativity gradually earn her the respect of her classmates, particularly after she begins to experiment with unique pastry designs that reflect her individuality.

Key characters include Riku, a talented but aloof classmate who initially dismisses Tamago but later becomes one of her strongest supporters. Riku's own struggles with perfectionism and familial expectations create a parallel to Tamago's journey, and their evolving relationship adds depth to the story. Another significant figure is Aya, a rival who embodies the conventional ideals of beauty and success. Aya's initial antagonism toward Tamago stems from her own insecurities, but over time, the two develop a mutual understanding and respect.

The plot explores themes of self-acceptance, perseverance, and the redefinition of beauty. Tamago's growth is not only professional but also personal, as she learns to embrace her unique qualities and challenge the narrow standards imposed by society. Her creations, which often incorporate unconventional ingredients and designs, symbolize her journey toward self-expression and empowerment.

As the story progresses, Tamago participates in a high-stakes baking competition, which serves as the climax of the series. The competition tests not only her technical skills but also her ability to stay true to herself under immense pressure. The resolution of the series highlights Tamago's transformation from a marginalized individual to a confident and respected figure in the culinary world, proving that true beauty and talent transcend superficial judgments.