Tintin is a liberator. He will forge a deep friendship with Chang, this orphan will be collected by the host family; Chang will be the same at the origin of "Tintin in Tibet".
Tintin is a humanist. He fights against drugs, the creators of poverty, artificial dependencies, as he will do later with the "Crab with the Golden Claws" with Captain Haddock, lost in drunkenness.
I recommend reading this beautiful book of adventures, where laughter squabbling with emotion teenagers. Create a friendship with another, beware of artificial pleasures whose true face is that of madness (drugs): the statement is radical.