From: CalvinbalI | #035
So perhaps some sort of severed hand did both. Whether it was Krauss/Natushi/Genji holding the hand in their own, or some device operating the hand that has remained undetected, either satisfies the red truth that has been established. So take that Erika, I’m smarter than you.
Assuming you're through that scene, me thinks you missed something:
No one in the mansion placed the letter in the hallway. This includes doing so by all concepts, such as directly, indirectly, intentionally, coincidentally, and unintentionally.
It was impossible for anyone outside the mansion to influence anything inside the mansion around the time of the family conference.
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