Despite Madam Tetsuori's explicit forbidding, Kanoko manages to sneak into Mina's room where they can be together without raising suspicion, or so she thinks. Perhaps the her guards are turning a blind eye to all this in quiet support of their relationship, not that they would ever admit to this.
Both versions of this pin-up are canon.
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Tier 1 >3. Comics>1.Original Works>Futa Escort Series>2. Singular Images>Main Series