From "Across the Nightingale Floor", book one of Tales of the Otori, by Lian Hearn:
Towards evening, the rain began to fall again, and it became a little cooler. Kenji and Shigeru were engrossed in a game of Go, Kenji being the black player. I must have fallen completely asleep, for I was awakened by a tap on the door, and heard one of the maids tell Kenji a messenger had come for him.
He nodded, made his move, and got up to leave the room. Shigeru watched him go, then studied the board, as though absorbed only in the problems of the game. I stood, too, and looked at the layout of the pieces. I had watched the two of them play many times, and always Shigeru proved the stronger player, but this time I could tell the white pieces were under threat.
....
They continued to play Go until late into the night. I could not bear to watch the slow annihilation of the white player, but I could not sleep, either, my mind full of what lay ahead of me, and plagued, too, by suspicions of Kenji.
This quote from book two, "Grass for his pillow" has nothing to do with Go, but I thought those with wooden go bowls might appreciate the description...
When he returned, he was carrying a small paulownia-wood chest, which he set down carefully on the floor. He left the room and returned three more times, each time bringing a chest or box. Each was of a different wood, zelkova, cypress, cherry, polished so that the color and grain spoke of the long life of each tree, the slope it had grown on, the seasons of hot and cold, rain and wind, that it had endured.
did they ever reveal the phantom opponent? Was it Venom? 
