Author's Notes:
Some things change... and some things don't.

A drabble riffing on this Unconventional Courtship Generator summary:

250) His Counterfeit Condesa by Joanna Fulford

The Major and the wild English rose

Major the Seventh Doctor does not approve of Wellington sending a woman on a perilous mission across French-occupied Spain, but he can see that Miss Peri Brown is no ordinary miss! The marriage-shy major and the English rose must pose as the Conde and Condesa de Ordoñez, travelling to a high society ball, and soon Seven doesn't know what is more dangerous — the menacing shadow of French patrols, or the sensual torment of sharing a room with this tantalising beauty…

In spite of the summary, Seven & Peri, not explicitly shippy.

"You weren't always this shy," said Peri, struggling with her silk stocking. "Heck, you helped me put on my corset for Kew Gardens. Which you still owe me, mister. So what's with the sudden attack of modesty?"

"What will the innkeepers think?" said the Doctor, covering his eyes.

"They think we're married, remember?"

"That's just it," he admitted. "I don't want Ace to find out I've been pretending to be married. I'd never live it down."

"So no help getting dressed, then?" Peri sighed. "Typical. I am never going to Spain with you again. And I mean it this time!"