She asked him if he would like to spend the time after work together, and he knew that this most likely ended them spleeping together (since they had an affair since more than a year). He pretended to have an urgent work to do, thus appologizing to be to busy tonight. Unexpectedly, however, he managed to do the urgent work quickly, and was finished with everything already half an hour later.

So he was happy about the free evening, that allowed him to watch another episode of “Sex and the City” in TV.