High heels make females look sexier through physics/mechanics, if you like. They tilt the pelvis forward, accentuating the swing of the hips and drawing attention to the bottom. As well as making the wearer appear taller (possibly suggesting genetic/survival superiority), they also accentuate the calf muscles, giving the illusions of strength as well as a pleasing shape.
I love my red 10cm stillettoes, my 9cm black toe peeper stilletoes, my 10cm stillettoe boots...