What is the main setting in the novel, A Wild Sheep Chase?

The story takes place entirely in Japan, although the location within the country changes. It begins in Tokyo, where the man has an advertising agency. Following a visit from a strange man who holds a position of power and authority, he travels to the country to the home of the Boss, which is described as an architect's nightmare. A combination of modern, western, and ancient Japanese buildings, the Boss' place is unique and speaks of vast amounts of money. From there, the main character and his girlfriend travel to Sapporo, a city in Japan, where their search for the sheep begins. They stay at the Dolphin Hotel, a small rundown inn that used to be the Ovine Hall. After meeting the Sheep Professor who tells them the location of a sheep villa, they travel to the Hokkaido region of Japan, which is an area of thick forests, cold weather, and mountains. Within the region, they find themselves in Junitaki, a small, dying town that appears to lie just below the place that is the focal point for the sheep. A caretaker for the sheep farm takes the couple to the villa of the sheep, owned by the Rat, located three hours north of the town, which is up the mountain over dangerous terrain. After learning that both the sheep and his friend, the Rat, is dead and setting up the death of the last powerful member of the empire, the main character travels back to his hometown to give J the respect he deserves.