Giffard Creme de Peche (peach) liqueur is one of their sweeter styled ("creme" liqueurs usually being sweeter in profile) liqueur having a "fresh and pleasant" aroma of peach. They suggest drinking as an aperitif (before-dinner) drink or with champagne.
Giffard is a French company specializing in a wide variety of liqueurs and eua-de-vie among other products. Some of those extra products are flavored cocktail syrups (or "sirop"). They are generally sweetened with pure cane sugar.