Oichi, younger sister of Oda Nobunaga, is renowned for her beauty and cherished by her brother. Her marriage to Azai Nagamasa, who loved her instantly, forged a political alliance between their clans. She embodies elegance and grace, the Yamato Nadeshiko ideal, often participating in dances with figures like Kicho and Nene.

Historical accounts within the series describe Oichi sending Nobunaga a sack of beans tied at both ends, a cryptic warning of the impending Azai-Asakura attack, though the event's accuracy is sometimes debated. After Nagamasa's death at the fall of Odani Castle, Oichi returned to the Oda clan with her three daughters. She later remarried Oda retainer Katsuie Shibata. Following Nobunaga's assassination and Katsuie's defeat by Hideyoshi Toyotomi at Shizugatake, Oichi remained with Katsuie as Hideyoshi besieged Fukui Castle, dying alongside him when the castle burned.

Oichi is occasionally noted for her preference for muscular men, and her relationships significantly influence the narrative's political dynamics. Her story navigates loyalty, familial bonds, and personal sacrifice amidst the turbulent Sengoku period conflicts.