SHE has spent the past 36 years comfortably nestled under the elegant cloisters of the world’s oldest monarchy. Surrounded by all the history and art of the Chrysanthemum Throne, she has been chauffeured everywhere by limousine, constantly waited upon, and brought up among the most elite cliques of Japan.

And now, in what may well be the most spectacular piece of reverse social climbing ever, Princess Sayako will abandon the life of sprawling palaces and ancient privilege for a smallish Tokyo apartment and a new home with the bespectacled bureaucrat she loves.

Sayako, or Princess Nori as she is popularly known, has 72 hours left to her as a royal member of the Japanese Imperial family. On Tuesday, and in accordance with the law, her marriage to the commoner Yoshiki Kuroda, 40, will instantly snatch her out of the world in which she has grown up and drop her into one experienced daily by 128 million ordinary Japanese.

Most Japanese brides spend a few weeks after their marriage practising their new signature but Sayako’s strange conversion to commoner poses a unique twist on that. She will lose the single-word honorific name Norinomiya and in three days she will have a surname for the first time in her life.

No member of the royal family has married a commoner since 1960 and the other immediate changes for the cosseted Princess will be dramatic: Sayako Kuroda will drive a car, do the weekly shopping and cook for Mr Kuroda. Sources have suggested that the Princess has already developed a knack for making Chinese food but also that she is quickly brushing up on a few more basic kitchen skills.

She will have a postal address and her name will appear on Japan’s official residency registers for the first time. She will have to be careful about money and tightly control the family spending of her husband’s modest Tokyo Metropolitan Government salary of about £35,000 a year. Once she has flown the imperial nest, Nori will share the somewhat mundane hobbies of her spouse, which apparently include “driving cars”.

Japanese media reports suggest that the Kurodas will be moving to a large new apartment block in the Mejiro area of north Tokyo within sight of the Gakushuin University campus they both attended. Each flat costs about £500,000 and it will certainly be a nice home, but considerably smaller than the flats in which many middle-ranking expatriate bankers live.

The block is near Mejiro forest and part of its attraction is the possibility of some balcony bird-watching. Until she quit in June, Sayako’s job was as a researcher at the Yamashina Institute of Ornithology, where she studied kingfishers.

In keeping with historic practice, the Government will make the couple a one-time gift of £750,000 to ensure that the former princess “retains a decency appropriate to her birth”.

But faced with this extraordinary backwards fairytale, Princess Nori is hardly making the most of her last few days of royalty. There will be no last hurrah of imperial pomp or pageantry as she marries Kuroda: with the exception of the rather well-heeled guest list and the timing of the event to coincide with the supposedly luckiest day of the Japanese year, the wedding will be a deliberately humble affair. Both the traditional Shinto ceremony and the afternoon reception will be held at the Imperial Hotel — a venerable location about half a kilometre from the Imperial Palace, and a place where many ordinary young Japanese choose to get married.

As far as details of the big day are known, the Princess will be married in a Western-style wedding dress and change into a kimono for the afternoon reception. There will be no cutting of an opulent cake and, in a major break with tradition, the bride and groom will enjoy the French meal on the same table as their guests rather than sitting in lonely segregation on a separate table before a giant golden screen.

Sayako’s parents, the Emperor Akihito and Empress Michiko, with the two princes and their families, will join about 150 guests for the event. Shintaro Ishihara, the Governor of Tokyo, is going along — not as a piece of political kudos by Sayako, but in line with the Japanese tradition of inviting the groom’s boss.

While the sudden loss of her royal title will be a wrench for Sayako, Empress Michiko has also spoken emotionally about her daughter’s flight to life outside the palace. Sayako has lived with her parents for 36 years and is known in the imperial household as a cheerful influence on a family that has not been without its trials.

She is known by her parents as “Miss Nevermind” — the phrase she used to calm her mother in times of stress — and the Empress recently said: “How fondly we will remember and miss this tender and heart-warming “Nevermind” in the days to come.”

DIFFERENT WORLDS

The Bride
Name: Norinomiya
Age: 36 Born with a silver spoon? Her parents are Emperor Akihito and Empress Michiko
Humble abode: The Imperial Palace, Tokyo
Best read minds: Studied Japanese language and literature at Gakushuin University
Hard day’s graft: was a researcher at Yamashina Institute of Ornithology Salary: unknown
Hobbies: Traditional Japanese dance, tennis, training guide dogs
Concorde or camper van? A limousine
Described as: “Tranquil and patient, took responsibility for all her actions, and had a personality that rarely ever slighted others.” (Empress Michiko)

The Groom
Name: Yoshiki Kuroda
Age: 40
Born with a silver spoon? His late father was a manager for Toyota
Humble abode: A flat he shares with his mother in Shibuya, Tokyo
Best read minds: Studied Law at Gakushuin University
Hard day’s graft: is an urban planner for Tokyo Metropolitan Government
Salary: about £35,000
Hobbies: driving cars
Concorde or camper van? Uses public transport
Described as: “Performing thankless jobs out of the public eye” (co-workers)

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