What are the themes and the psychological traits of the characters in “In Praise of Shadows” by Jun'ichirō Tanizaki?

The primary themes of this 1933 essay are nostalgia and the superiority of traditional Japanese aesthetics. As the work is nonfiction, there are not any characters per se. The entire essay consists of Jun'ichirō Tanizaki’s opinions so the narrator occupies the role of the central character.
Following the 1923 Yokohama earthquake, Tanizaki—primarily a fiction writer—moved from the city to Kobe, a neighborhood of Kansai, which was considered to be one of the country’s most traditional areas. Increasingly pulling away from the Western-style modernization that was making inroads in Japan, Tanizaki everywhere sought the persistence of the older principles of beauty. While the essay is especially concerned with architecture, this concept extends beyond design and construction of buildings. It encompasses lacquerware, theater, color palettes, lighting, and landscape; the tiniest details, he says, are noteworthy. Tanizaki, who continued to wear kimono, also addresses personal appearance; his praise of female style centers on the courtesans’ exaggerated style, including shaved eyebrows and white makeup that vastly differs from Western norms. The striking contrast between Japan and the West is everywhere obvious, but the author tends to overlook differences within Japanese society and, in concentrating on female appearance, to convey the primacy of a male gaze.
As Tanizaki is primarily concerned with harmony and appearances, he is an aesthete. As he is so deeply steeped in the values of the past, idealist and escapist are some of his prominent psychological traits. The author refers to Japanese, other Asian, and Western writers and thinkers; notable among these are the actors Kongō Iwao and Baikō, the Buddha, Confucius, and Albert Einstein.
The standard English translation by Thomas Harper and Edward Seidensticker was published in 1977. The 2017 illustrated re-publication in English, translated by Gregory Starr, includes contributions by Kengo Kuma and Eve Zimmerman.
http://www.sorabooksjapan.com/inpraiseofshadows.html