The thing is, K was staying with a friend last night, and Bob was down the hill watching a DVD and drinking ale with a neighbour, so it was only the SS and I.
So when, just as I was climbing into bed, I discovered I'd left my book on the stairs ('The History of Love' by Nicole Krauss. Have you read it? You really should; it's hauntingly good), it seemed pretty safe to sprint smartly down to get it. Naked.
Bob really must have come back very quietly. Why he chose that moment to emerge from the sitting-room is beyond me. The sight of his father retreating up the stairs trying to create the illusion of underwear with his bare hands seems to have been a bit of a shock. He was unusually quiet this morning, and seemed almost eager to get to school.