Suenaga Misuzu is a high-class woman possessing significant political and financial connections born of her past affair with the late politician Seishirō Kuroda. This relationship produced her daughter, Mimi Suenaga. She later marries Kintaro Yajima, the series' protagonist.

As the proprietress of Jardin, an exclusive Ginza club, she navigates influential social circles. Her background and connections intersect with corporate conflicts involving Yamato Construction, particularly following its merger and restructuring, where her insights and associations remain pertinent.

Her character maintains continuity across various adaptations, including manga, live-action films, television dramas, and anime.