The Lion, the Witch, and the Wardrobe book cover
Lucy and Susan soon recognize that the boy is Bacchus, whom they had learned about from Mr. Tumnus long ago. The fat man is Silenus. (If you've seen the original 1940 version of the Disney movie Fantasia, you may recall the scene of the fat man on a donkey during Beethoven’s Pastoral Symphony. Disney basically morphs Bacchus and Silenus.
|Sivenus and young Bacchus from Feast of the Gods (Bellini) Wikipedia|