Megumi Wakao, widow of Wakao Kazuma, inherited a substantial estate including valuable paintings after her husband succumbed to heart disease. Her stepson Kyousuke, the sole heir, moved to evict her, disapproving of her past relationship with his father. To secure her residence and gain possession of the paintings—especially Kazuma's masterpiece "The Yearn of the Morn," tied to her unforgiven grievance against him—Megumi proposed an exchange. She offered Kyousuke unrestricted control over her daughter Yuna, his stepsister, in return for resolution of inheritance tax issues and transfer of the artwork.

She initially adopted a cold, calculating demeanor to negotiate from strength. This facade shattered upon witnessing Kyousuke's sadistic exploitation of Yuna. Overwhelmed by guilt and regret at the severe consequences of her proposal, Megumi attempted to retract the offer involving Yuna. She sought to substitute herself in Yuna's place, hoping to mitigate the harm. However, her intervention came too late; Yuna had already embraced the sadomasochistic dynamic with Kyousuke willingly.

Unexpectedly, Megumi discovered a latent compatibility with Kyousuke's dominance, gradually developing a submissive inclination mirroring her daughter's. This shift suggested an underlying familial predisposition toward such dynamics. Her physical appearance features shoulder-length blonde hair, amber eyes, and a mature presentation.