The books by MIYABE Miyuki that I've discussed here have been nearer to crime novels than to the traditional idea of a mystery. ステップファーザー・ステップ (steppufāzā steppu, Stepfather Step, 1993) is a set of lighthearted traditional puzzle mystery stories, with the same characters. These are the narrator, a professional thief, and two middle school children, identical twins Satoru and Tadashi, who pick him up after he falls off a roof. The twins have been abandoned by their parents, who have each separately run off with a new partner, and are trying to get by alone rather than letting the state take them into its care. The money however is running out and they think that the thief can help them make some more. Gradually over the course of several stories, the thief comes to be a kind of replacement parent for the children. The book was made into a television series in 2012.
The actual mysteries use clues and tricks like those of golden age detective stories, but still fairly loosely plotted, with more emphasis on parts of the story incidental to the puzzle. The mysteries generally involve serious crimes, such as attempted murder and kidnapping, but occasionally the stories turn on a non-criminal mystery. The setting reflects modern everyday life, but the humorous approach is treated as a licence to include much that is unrealistic or deliberately absurd. The book was an easy, light read, but the mixture of humour and sentiment didn't always work for me. It felt like there was some sort of emotional satisfaction that readers were meant to get from the book that passed me by.