Charlotte's nickname among the wags at university was the Duchess, but it was only when I saw her parents' house that I realised that it was based in truth.
The approach to the front porch, through a gatehouse and avenue of poplars, took five minutes on my bicycle. By the time I reached the colonnaded portico I was in awe and a little out of breath. It was the final stretch of a seven-mile journey from the nearest station and I was regretting having made it in my rented dinner suit.
I rang the bell and shifted uneasily from one foot to another in shoes that were some way from being worn in. I could see no other party guests and anxiously guessed that turning up early had been a mistake.
The statuesque woman who answered the door put me at my ease. "You must be Robert," she said. "I'm sorry about the dressing gown. The staff are all busy in the kitchen and you caught me getting dressed."
She extended a hand. "Anna. I'm Charlotte's mother. Come."
She beckoned me and the way into a hall, the tails of her silk gown billowing behind. She called for her daughter. "Darling, your first guest has arrived."
Charlotte's voice came back irritably. "I'm not ready, mummy. Tell them to wait."
Anna smiled and gestured for me to go up the stairs.
"I'm sending him up. I don't think he's ready, either."
To me: "Down the corridor, third on the right."
I meant to ask whether it would be better if I waited downstairs, but she was insistent. "See you at the party," she said.
When I reached Charlotte's bedroom she was clothed in splendour and sitting at her dressing table, peering at herself as she glossed her lips. My knowledge of period costume is sketchy at best, but if I had to guess I would say that her dress was of the sort you might have seen on Marie Antoinette.
Charlotte didn't turn round but glanced at me in the mirror. "Robert, I might have known," she said. "Fashionably early, are we?"
I started to apologise but she spoke again. "Don't worry. It's just as well. The other guests will be arriving soon and you don't want them to see you like that."
She looked amused. I blushed. The invitation had said that the dress code for the ball was "finery" and I immediately thought of black tie.
"Dinner jackets are for dinners, darling. If you're going to be all straight about it then you should at least have gone for white tie and tails."
She got up and strode towards me. I made a half step towards her to kiss her on the cheek but she gave me a gentle push with a lace-gloved hand as she walked past me to the door.
"Mummy" she called. "Have we got one of Olly's tailcoats?"
"He's taken everything with him to Scotland," Anna called back, referring, I guessed, to Charlotte's older brother. "Is it for Robert? I may have something for him."
Charlotte sighed. "Come on, then," she said to me. I trailed after her along the corridor to her mother's bedroom. "In there. I'm going to finish getting ready."
I crossed the threshold and waited. Anna was out of sight in an adjoining bathroom. "Tell him to take off the dinner suit," she said.
I hesitantly took off my jacket and cummerbund, shoes and socks. I deliberated over the rest and decided to remove the trousers but keep my shirt and boxer shorts.
"Have a look in the top drawer," she said, still invisible. "There should be something suitable in there."
I was about to explain that Charlotte had gone but decided to look in the drawer. It was heavy and stiff and when I got it moving it came suddenly and spilt its contents to the floor.
Dozens of pairs of knickers fell at my feet. I crouched to gather them up, blushing at the intimacy of it.
I could tell they were expensive. As I put them back I felt the silk and lace between my fingertips. It was a sense of the forbidden that I couldn't help but find arousing. I got the last pair in and realised as I stood up to replace the drawer that my excitement was showing.