Engaged to the Unidentified

She's Their Birth Mother?! (1x5)

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Kobeni learns about a member of the Mitsumine family coming over, along with the fact that Mashiro is nine years old. Whilst shopping for supplies for her guest, Kobeni comes across a young woman who had gotten lost on her way somewhere and helps her out. This woman turns out to Mashiro and Hakuya's mother, Shirayuki, who casually lets slip that their family isn't human. This causes Kobeni to have another fever as she remembers more things about her past, where Hakuya was allegedly a dog. Shirayuki later tells Kobeni that her constant fevers are the result of Hakuya giving her half of his inhuman power to save her life. Before taking her leave, Shirayuki gives Kobeni her thanks for treating Hakuya well, mentioning how he picked up his habit of stroking her head from her.