Why is it comical about the appearance of the lean and slippered pantaloon?

The comical aspect of the lean and slippered pantaloon lies in the contrast between his former status as a respected figure in society and his current state of being aged and feeble. The image of him wearing slippers emphasizes his old age and implies a certain laziness or lack of vigor. This contrasts with the idea of the powerful and dignified figure he once was, making it humorous.