Connections with The Wind-Up Bird Chronicle and Hard-Boiled Wonderland and the End of the World
Spoiler warning: Plot and/or ending details follow.
Towards the end of the Kafka on the Shore, the protagonist Kafka Tamura has intercourse with his supposed sister Sakura in a dream he enters while waiting in the isolated hut. Later on, this dream is verified also by her. This is highly similar to the hotel scene in which Toru Okada, protagonist of The Wind-Up Bird Chronicle enters through the well. At the end of the book, the village where Kafka gets to through the entrance in the forest, is directly a copy of the town of the Hard-Boiled Wonderland and the End of the World with the bookless-library and the memories stored in there. The half-shadow issue also finds its correspondence (as well as its explanation) in Hard-Boiled Wonderland and the End of the World. Also, the two characters Mrs. Saeki and Oshima of Kafka on the Shore can be considered as the mirror images of Akasaka Nutmeg and her son Cinnamon Nutmeg of The Wind-Up Bird Chronicle.
Spoilers end here.