If she keeps the gift, it means she will marry him. It was a popular belief that if young girls wrote their boyfriend's names on bits of paper, rolled each name in clay, dropped the clay in water. The first scrap of paper to rise would have the name of her true valentine. Another superstition among young unmarried girls was that, if they pinned five bay leaves to their pillows on the eve before Valentine's Day, one leaf to the center, and one to each corner then they would see their future husband in their dreams. Many people give candy to their sweethearts on Valentine's Day.
Candy is sweet and so are sweethearts.
In North America and Europe, chocolates are sold in fancy boxes shaped like hearts. Some boxes have flowers and ribbons on them.