Sonya is 162 cm, athletic, and easily the fittest woman on this list, which she is entirely matter of fact about. She wears dark brown hair long and straight, has hazel eyes, and dresses with the economy of somebody who worked out what suited her a decade ago and stopped experimenting. Early thirties. There is no fuss about her arrival and no performance in it either, which people notice within about a minute.

English, spoken plainly and with a good deal of dry amusement underneath. She has travelled more than anybody here and very little rattles her as a result. She trains most mornings, cooks the same six things extremely well, and has an unfashionable enthusiasm for long walks in bad weather. She is easy to be quiet with, and better than almost anybody at telling when a guest wants company rather than conversation. She is not a woman who needs telling anything twice.

Her SW1 evening is an early one by preference. Signor Sassi on Knightsbridge Green suits her exactly: an Italian room that has been there forever, staff who look after people rather than perform for them, and a seven o'clock table that means you are not rushing anything. SW1 has been her postcode for a decade, which makes the walk up to the park, or back to your hotel, short and entirely uncomplicated.

Early tables and clear finish times are the point of booking her, not an apology for it. The Knightsbridge page lists SW1 and everyone else covering it. Ask the desk about a particular evening, with the hotel, and what is left this week will be spelled out plainly.

Nothing has been written up under Sonya yet, which is usually what discretion looks like. A note goes on the board only when a client sends one in writing, she agrees to it, and the office has checked that it reads as a first name, a month and nothing private.