Chrístõ and Hext’s Dinner Date is the epilogue to The Lives of Chrístõ Mian. It ties up the last loose ends. I felt something was needed before Chrístõ left Gallifrey.
The reason for the ‘date’ goes back to the story ‘Sisterhood of Karn’ which went online nearly a year before this one. It was the story before the Christmas one of 2007. It doesn’t seem that long, to be honest. But a lot has happened for Chrístõ in that time. In ‘Sisterhood of Karn’, however, readers might recall these lines:-

“Do you think one day me and you could meet up in the Capitol and go and have a quiet lunch at the Conservatory, instead of always being in the thick of something sinister?”

Chrístõ laughed. “Are you asking me out on a date, Hext?”

Ever after, when the two have crossed paths, the ‘date’ has been referred to, and I fully intended, originally, that it would take place at the Conservatory, which is a restaurant in Gallifrey’s capital city which I introduced as a fashionable eatery in the Marion and Kristoph stories. However, the stories about the Mallus invasion implied that a lot of the city was damaged and it didn’t feel right to show a restaurant doing business in the immediate aftermath of the disaster. On reflection, it is entirely possible it would be. A lot of restaurants in Paris opened to joyfully celebrate the city’s liberation from the Nazis in 1945, after all. But I had a better location for the ‘date’ by then.

The Tower of Silis Bonnoenfant was inspired by a piece of science fiction artwork on the internet. It became the backdrop to three Marion and Kristoph stories in which Marion met Silis, then it became the Headquarters of the Time Lord resistance to the Mallus. With Silis dead, though, I wanted a use for the tower simply because it is such a great invention. And I hit on the idea of Hext actually moving into it, first as a refuge, and later, as he suggests, as a place where he could rebuild the Celestial Intervention Agency.

The Celestial Intervention Agency does seem to become a sinister organisation by the time of the Fourth Doctor’s Deadly Assassin adventure. By then, we must assume, Hext has lost control of it again. But for now, the agency is in the hands of somebody Chrístõ knows and trusts, and that has to be good for him.

Killing off Malika Dúccesci, who the two had clashed with in Sisterhood of Karn was an afterthought. And I remembered later that a boy called Dúccesci challenges young Christopher de Lœngbærrow in the New Lords of Time story Christopher Remembers. But there is no reason why he can’t be a younger child born of Malika’s father to replace the lost heir.

Chrístõ, of course, declines the offer to join the new Celestial Intervention Agency. He has to. He has responsibilities back on Beta Delta IV. But I fully intended for him to think about it seriously for a little while. The idea of him buying a home of his own and actually settling, by choice, on Beta Delta IV for a while, however, opens up some new possibilities for future storylines.

http://en.wikipedia.org/wiki/Celestial_Intervention_Agency