While I was out walking a few months ago I met a family with a little girl. "Where's your dog?" she demanded. When I told her I didn't have a dog she turned to her mother and said, "He must have an imaginary dog!"
The only people I saw on my rainy walk this morning were two men with dogs. So lets say I had an imaginary dog - I wouldn't want you to think I'm completely mad.
If you want to meet my imaginary dog, just wait there in the rain; he'll be along soon.