Corrected entry: When Eustace is transformed into the dragon Edmund and the prince see his clothes burning to ashes implying that he was transformed without clothes. When the lion transforms him back into a boy, he is suddenly wearing clothes again. Only his shoes are missing, which were burned too.
Correction: A magical talking lion, who is this world's all-powerful deity, magically transforms a boy who had previously been magically transformed into a magical beast back into a boy, and your suspension of disbelief falls apart when this omnipotent god who created the very world they're in out of nothing magically gives the boy clothes so he won't be naked in front of everybody? Nope, sorry, this isn't a mistake.
Phixius ★