What drives Winterbourne's concern with Daisy's sexual behavior?

Winterbourne visits his aunt because it is proper. He is often persuaded by her opinions though cannot take the harsh view of Daisy that she holds because he finds Daisy extremely beautiful and innocently sweet, a product of her homeland. Still, he is swayed toward believing Daisy is improper because of her indiscretions with Mr. Giovanelli. He finally tells her that he does not care what she does with her life. After her death, he realizes that his final judgment of Daisy was incorrect. His first impression of her innocence and love for life was more on target.