A 14yo girl with fully developed secondary sexual features is sexy, and indistinguishable from an adult. Exploiting her for sex or sexual gratification is wrong because she is a child with a child's brain, but don't lie to your eyes and say big titties on a cute body with a young face and child-bearing hips isn't the very embodiment of sexiness. Tits don't suddenly become sexy at the age of consent.
Not that that matters here, because drawings aren't people, and an adult dressed as a child is as much a child as a child dressed as an adult is an adult.