She's pushing Cupid back, but is really just playing with him. Youth flirting with adulthood, maybe? I also like the composition of this painting. If you follow the lines of the girl's legs and lower body, then her upper body, head, and the top of the tree above her, you see a bow shape. A parallel bow shape is described by Cupid's body a... (See the whole comment)
Very good analysis of the painting. Often it is said that Bouguereau's paintings have little composition but I find that the amount of compositional thoughts he gave to his paintings is more than meets the eyes.
Do you have any more information about this painting... like where could I get a hi-res image of this painting?