The diary is that of Mr Pooter, a middle-class man with social pretensions. Other characters include his wife, his son Lupin, his friends Mr Cummings and Mr Gowing, and Lupin's unsuitable fiancee, Daisy. The humour comes from Pooter's unconscious gaffes and self-importance; he believes himself to be witty with a good sense of humour, but he is in fact utterly humourless.
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