Dustin lifted the two bottles up to your lips before he could think much more about it. It's just too easy to ignore the little voice in the back of his lust-filled mind that screams at him to stop. The two liquids bubbled as he swallowed them. He groaned and coughed as he felt his insides burning.
Every muscle in his body started pounding and throbbing as his clothes began to tear. His body grew more and more massive, filling with massive muscles. His hairs kept growing into a thick pelt of black fur, so dark that they seemed to suck up the light, with red highlights on his chest, head and legs
Dustin howled with pain as he felt his bones grow to a more proper shape, arms lengthening as his ribcage barreling out to a bestial proportion. His previously short claws pushed outward into deadly black things. His hands grew several times larger and morphed into paws covered with dark fur. His feet did the same; his toes were stretching while gaining wicked black claws. With a loud creaking and popping, his ankles pulled up towards his knees. He lost his balance and fell backwards, his hips shifting to allow for two and four-legged movement, his arms quickly gaining the needed muscle to support his still-growing form.
He was now becoming something never seen before on this world, most would have said “abomination” or “monster” but to him it’s a new beginning, a necessary step in order to satiate his new desires. He roared with a mix of pain and delight as he was swelling with power as the demonic beast corruption in him grew stronger. His human tooth changed into wicked fang, filling and finally overflowing his still human mouth.
“Hhgh….rruhrrhhh…” Dustin groaned as the fur rushed up towards his head, his jaws creaking as it slowly moved forwards, turning into a muzzle adorned with razor-sharp fangs, some of them still too big for his mouth.
His jaws stretched further, nose sinking into his upper jaw as the nostrils flared, expelling smoke. Saliva dripped from his fangs as his tongue grew longer and thicker to fit his new maw. His vision blurred for a moment as his eyes moved to the sides of his head, pupils dilating as his eyes turned a feral red with a faint glow.
Huge roars blasted out of his drooling maw. The pulses only got more intense, his entire body pumping and throbbing larger, filling the room more and more. His mind was falling into constant depravity, twisted by the pleasure of the transformation. His dick grew with each thump of his heart as he furiously stroked it, each stroke releasing massive burst of pre-cum.His cock continued to bulge, turning into something more bestial than human, his ballsack swelling as his testicles grew larger and larger.
His body won’t stop growing, his bones elongating and becoming stronger and denser. Dustin has the constant urge to keep growing bigger and more monstrous. He felt a pain in his spine as a long tail pushed out and grew red spikes all the way to the tip, which was a sharp point. Sharp spikes grew on his back until they stopped at his head which now had a set of wicked horns. Other spikes burst from his shoulders and heels. Finally a red glowing pentagram appeared on his forehead, between his horns.
Dustin let out a deafening roar exploded as he finally stood in the room, the walls began to creak and groan as his body was pushing against them.
(continuations are welcome)