There are three major characters in The Tin Flute. The main character, or protagonist, is Florentine. Florentine comes from a poor family. She works hard to help her family make ends meet. Florentine is a noble, sympathetic character. The second major character in the book is Jean. Jean is ambitious, cold and calculating. Florentine falls in love with Jean but Jean treats her cruelly. He decides that she is doomed to a life of poverty and so abandons her. At the end of the book he takes advantage of Florentine's feelings for him, and he has sex with her against her will. The third major character is Emmanuel. Emmanuel is a friend of Jean's, but he is a kinder, simpler character than Jean. Emmanuel falls in love with Florentine and at the end of the book. Florentine, pregnant with Jean's baby, agrees to marry Emmanuel.
As might already be clear from the above outline of the three major characters, the plot of the story is rather tragic. It begins with a sympathetic protagonist trying to escape poverty. There is, in the middle section, some hope that she might do so, but this hope is tangled up with, and destroyed by a doomed romantic relationship. The protagonist at the end of the story decides to make the best of what she has and marries a man that she doesn't love.
The main ideas in the story are about poverty. The story suggests that poverty imposes severe limitations upon individuals. Florentine is forced to work long hours for little money. Her opportunities to escape her poverty are very limited, and thus her life is without much hope. When Florentine decides to marry Emmanuel at the end of the story, it is because Emmanuel represents her only opportunity for financial security. Poverty thus not only dooms Florentine to poor living conditions and long working hours, but also to a loveless marriage.