Adjacent includes diagonals. Book knowledge required. This is hard but is absolutely possible without guessing. Be warned that after the first 4 boxes, you will need to use almost every clue you've had so far to apply multi-step logic in order to place the next two characters. Walkthrough in the source if you get stuck, and sometimes the characters will give you hints about which clue to reconsider or which character's placement to look at next. Please let me know if there are any issues!
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