Wakasa was the legendary kage no seisai ("shadow wife", essentially the secondary wife) of the now-disbanded Hogougumi's kumicho, Sou Mikaido. Fourteen years after her death, she is still regarded as a legend in the gokudo world due to her outstanding fighting skills and speed, along with an intimidating presence. Wakasa's situation was exceptional among the gokudo; she had to handle the fighting responsibilities of being a kumicho's wife because the omote no seisai (primary wife) was too physically weak for it.
Wakasa was killed during the final confrontation between Hogougumi and their rival yakuza group, Garyukai.
Her relation to Hogougumi:
Despite rumors suggesting a strained relationship between Wakasa and the omote no seisai of Hogougumi, they were actually very close friends. The omote no seisai even convinced Wakasa to keep the child (Tsukasa) she had conceived with Sou. The video message Wakasa left for Tsukasa revealed that her relationship with Sou was tense. Sou pursued Wakasa relentlessly, leading her to agree to sleep with him once, hoping he would then leave her alone.
Wakasa felt compassion for Shiva, Sou's younger brother, whom the rest of Hogougumi ignored due to his terminal illness. She was one of the few who treated him kindly. Shiva perceived her sleeping with Sou and becoming his kage no seisai as a betrayal, which led him to betray Hogougumi. Fourteen years later, Shiva learned from Wakasa's video message to Tsukasa that Wakasa had never loved Sou but instead loved Shiva and wanted him to find peace.
Her relation to the Kozukis:
Wakasa and the Kozukis were close friends. Ikumi and Yutaka agreed to take in Tsukasa and raise her as their own should anything happen to Wakasa. After discovering her biological mother's identity, Tsukasa grew angry when people compared her favorably to Wakasa, feeling abandoned. However, after viewing the video message, Tsukasa understood that Wakasa wanted her to see the Kozukis as her true parents, leading her to respect Wakasa more for not trying to be maternal.
Despite claiming in the same video message that she initially wanted to terminate the pregnancy, Azuma recalled Wakasa being excited about seeing the person Tsukasa would grow up to be and hoping she would have a happy life.
