The aquarium
When Toru thinks of his love for his wife, especially the love they shared when they were just getting to know each other, he flashes back to give languid accounts of the jellyfish and others in the aquarium from their first date.
Jazz and cats
The book is undeniably jazzy. By admitting his affinity for jazz, Toru gives them permission to interpret the novel as a jazz project. The effect is that suddenly, the novel is a very noir, jazzy story about finding "cats," especially a bad cat named Noboru. The effect is sublime.
The abandoned house
Toru finds a friend at an abandoned, decrepit house. The house is like a feral cat colony. The imaginary son of Nutmeg, "Cinnamon" restores the house (in Toru's imagination), but Toru doesn't sleep in the house (even when he buys it), because he prefers to stay in the bottom of a well. The house is commonly described in shocking, confusing language.
Warfare imagery
An unlikely feature in this novel is the wartime account of Mr. Honda, as well as the additional remarks provided by Lt. Mamiya. The inclusion of brutal, gory imagery invites the reader to consider that perhaps underneath the story's silly, jazzy exterior, there is a titanic battle raging between witch and warlock: Kumiko versus her brother, Noboru.