(2) This curious expression has its origin in the Japanese saying that lovers "exchange pillows." In the dark, the little Japanese wooden pillows might easily be exchanged by mistake. "While the pillows, were yet not definite or fixed" would mean, therefore, while the two lovers were still in the habit of seeking each other secretly at night.
(3) Governor or local chief. The Bugyo of old days often acted as judge.
Kokoro: Hints and Echoes of Japanese Inner Life · The Wunder Library — complete classics, free to read, with narration.