What is ironic about the mural artist's portrayal of the story of Zeus and Europa?

In Classical Greek mythology, Zeus hatches a plan to seduce and/or rape Europa. She takes the form of a cow and he takes the form of a bull in order to woo her. It is worth noting that the two actions of rape and seduction were viewed as nearly interchangeable concepts within Classical Greek society. Therefore, the artist's portrayal of Europa as a cow with "long, droopy eyelashes" who gazes "back at the bull with sultry welcome" (26) is both ironic and disturbing, given the context.