I'm so sorry that our last lab test made you crave sucking cock. I'm sure that this serum will make that all better. Let me inject you with our new serum and... hmmm you just keep staring at the bulge in my skirt. Good just as expected.

What? You thought I was going to cure you of your craving for cock. Oh no. this injection was to make you crave cum on top of it. You're going to drop on your knees and suck my thick hard cock, milking it with your lips until I cum down your throat. You'll forget about pussy now. All you'll crave is cock and cum. This experiment is a success.