Fujieda Shiro is the owner and sommelier of the wine bar named Monopole. Within the story, he serves as a mentor to Miyabi and a trusted counselor to Shizuku, offering guidance as they navigate the world of wine. Despite his tendency to quickly remind Shizuku and his friends of their ever-growing tabs at his establishment, he is known for being very generous. This generosity is demonstrated through his actions, as he often brings out fine wines to treat his friends and provides samples to Shizuku whenever assistance is needed.

In his younger days, Fujieda studied wine in France, an experience that deeply shaped his expertise. During that period, he was also a member of student protest and communist movements, suggesting a past marked by political engagement and ideological conviction. This background adds a layer of historical depth to his character, implying a life lived with passion both for social causes and for the art of wine. His role in the story is primarily that of a supportive elder figure, using his knowledge and resources to aid the younger protagonists in their journey without directly fighting their battles for them. His notable abilities stem from his refined palate and deep understanding of wine, honed through years of study and practice in France, which he applies in his role as a sommelier and bar owner.