It's appealing for several reasons. The depth of the emotions portrayed, the unexpected twists in the story, and the beautiful art all contribute. It manages to create a world that you can't help but get lost in.
Fleas can indeed be a contributing factor to mange. Their presence on an animal's skin can trigger allergic reactions and infections that may result in mange. However, it's not the only cause.
It could be that the cartoon is set in a foreign place and the man has to speak the local language. Or perhaps it's for educational purposes to teach viewers about different languages.
Iranian political cartoons often focus on social and political issues within the country. They might use satire and humor to comment on current affairs and government policies.