I believe this is his aunt. Judging by the size difference and her clothes and loom of the character she's too old to be a sister or cousin. And the fact some younger aunts in Japan prefer to be called "Big Sis" to feel less old I'm guessing she's an aunt. If I am wrong please correct me but its an educated guess

If it was human male 😙👌

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@besh any word on the rest of Manbou Shoten's works?

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