Character profile
Sanae Izumi
和泉 さなえYuuhi
Biography
According to Wikipedia, Sanae Izumi is Minori's older sister and is always looking to join Mayuki and his friends on an adventure.
Story spoilers
She is later revealed as one of two "dolls" controlled by Seiran and uses a pair of claws when in her Aya or doll form.
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