Cupid (called Eros by the Greeks) is always causing trouble. He's the god of desire (and we don't mean desire for ice cream Sundays, if you get our drift). As you might know, desire is never simple. In Greek mythology, a sting from Cupid's arrow almost always means that something bad is going to happen – like, really soon.
In the story of "Apollo and Daphne," we see Cupid use his powers to get revenge on Apollo. We might almost sympathize with Cupid, here. After all, Apollo is a total jerk to him at the beginning of the story. However, Cupid seems to involve Daphne in his prank for no good reason, except that she was just conveniently around. This makes Cupid seem kind of carelessly cruel. Of course, no one ever said desire was fair.
For much more on Cupid, read up on him in our Cupid Files.