Suggestion for a children's book:

"The Further Adventures of Tom's Riding Lizard"

Despite the title, there's no previous entries in the series at all, this is the first book. Tom is never seen or mentioned beyond the title.

The eponymous riding lizard just wanders around a nice countryside in full tack, politely holding its reins in its mouth. Sometimes it solves a crime. Sometimes someone tries to ride it and it gently trips them with a tail and leaves the area.