Four young brothers, known as the Four Princes, are surprised when their father adopts an orphan girl named Fely, who they often fight at school.

Four young brothers known as the 4 Princes, are surprised when their father adopts an orphaned girl named Fely, whom they often fight at school. Although at first they can't accept their father's unilateral decision, as time passes they grow closer, and perhaps they realize that having a sister they can protect is the right choice.