Kotobuki Tsumugi is depicted in a graceful standing pose, embodying her calm, gentle personality from K-ON!. The figure features her signature long light brown hair styled in soft waves that frame her face and cascade over her shoulders. She wears a refined school uniform inspired outfit: a neatly tailored cardigan over a crisp blouse, a pleated skirt, and knee-high socks, with careful attention to folds and subtle shading that highlight the fabric texture. Her expression is warm and serene, with bright eyes and a small, inviting smile. She holds a compact acoustic guitar in her hands, its strings and sunburst finish captured with precise detailing. The base is understated, ensuring the focus remains on her elegant silhouette and character.

Kotobuki Tsumugi, often called Mugi, is the courteous and kind keyboardist of the K-ON! light music club. In the series, she brings a graceful air and a sincere passion for music, preferring tea and sweets and turning even casual moments into warm memories for her friends. A noble sense of responsibility and a gentle humor make her a steady presence in the band, supporting Yui, Mio, Ritsu, and Azusa as they navigate rehearsals and performances. Though she hails from a refined background, she grows close with her clubmates through shared practice, late-night conversations, and the rhythms of school life. This figure captures that sweet, supportive spirit and the quiet strength behind her smile.