You wake up, drowsy & disoriented, in what appears to be a medical laboratory. Nina appears to you in gloves and an apron, telling you that you're going to have a new, experimental procedure she's been working on. The first step is to test the sensitivity of your genitals - Nina pulls out a Wartenberg wheel first, pressing it's sharp spikes into the head of your cock, squeezing it painfully before jerking you a little to see how sensitive you are. Once she's determined you're a perfect specimen, she injects you with the mysterious serum, turning you into a monster! And the first thing to become monstrous, scaly, and fuckable.... is your dick! Enamored with your new monster cock, Nina sucks and fucks it eagerly in different positions, cumming harder for your newly transformed dick than she ever would have for your useless old human flesh.