He's grown another cock.

Concerned with his mother's mention of a "second effect", John looked down at his slobbery body and reacted with a startle. Sprouting from his crotch was a second, equally as large dick, and it was growing along with the first (now six feet long). He experimentally wrapping his fingers around it, and gasped. Sure enough, it was real.

The reptilian giant looming over him laughed, her numerous breasts jiggling. Her voice was deep, booming, and husky. "Surprissssssssed, my ssssssson? Every time you cum, you'll now get another one of thossssssse." She gently tapped the tip of his new appendage with the point of her claw. "And I plan to make ssssssssure you'll have plenty to sssssssspare!"

Excited by her own words, Julie groaned as the flow from her pussies increased and her cocks dripped copious pre-cum. On cue, her body once again began to transform. Crimson hairs appeared to sprout from her head like a tangle of vines. But, on closer inspection, they weren't hairs at all. Each strand was a living snake, writhing and hissing, growing longer and more numerous until the woman had a scaly mane that would make any gorgon envious. Again, her head lowered toward his body. It was larger than his entire body, now. If he wasn't weighed down by his seven-foot schlongs and yoga ball-sized nuts, he might have bolted then and there.

The hair-snakes slithered and twisted around him, lifting him up off the ground. Julie then rose up to her full height, with John suspended in the air a short distance from her face. Fifty-feet high, he was incredibly thankful he had no fear of heights.

"Oh, darling, your ballsssssss look sssssssso full." She feigned as innocent an expression as her features would allow, her voice dripping with teasing sarcasm like her fangs dripped with venom. "Don't worry, I know jussssssst what will fixsssss you right up." Two of the larger (and fortunately fang-less) snake strands positioned themselves in front of his cocks. As large as each dick was, now (eight feet long and two feet in diameter), John doubted the snakes could even handle him. But if the limbless reptiles were known for something, it was being very stretchy. They opened their mouths wide, attaching themselves to the tips of his penises. They gradually stretched and worked their way over the shafts, until both cocks were entirely swallowed up.

John groaned as the wet insides of his mother's appendages tightened around his lengths. Then their muscles started to squeeze and massage the stiff rods, eliciting loud cries of pleasure from the entrapped man. "Ohhh~. W-What the- How does it f-feel so good?" It was better than any blow job he had ever received. The snakes' muscles tensed and rippled down the lengths of his mighty cocks, acting like some kind of biological milking machine. John screamed, as in only a few seconds, he was already blasting two steamy loads into his mother.

A third penis rapidly grew up from the base of the other two, quickly reaching nine feet long. Another snake-hair immediately swallowed it and began working like the others. John couldn't stop moaning. He was under constant pleasurable ****, not afforded even a second of rest as he was already working towards another orgasm as his hips involuntarily bucked.

"Mmmmm, look at you, so helplesssssss within my grassssssp~" Julie's body shuddered. Her pussies, practically gushing fluid, plumped up until they formed incredibly inviting, soft mounds. She groaned as her prehensile cocks doubled in length, creating a veritable forest of virile tendrils. Her torso bulked out in pulses, increasing her strength ten-fold. Even her "hair" thickened, increasing the strength and dexterity of their muscles, only enhancing the pleasure John felt.

"Ungh!" John groaned, releasing more cum as he climaxed again. Another ten foot cock, again swallowed up by his mother. It wasn't long until he came again, and he was finally released. Five massive meat rods hung from his crotch, still hard as rocks as his mom's hormones worked within his body. He panted heavily, heart beat refusing to settle down.

"Yessssss! Now, you're ready!" Large enough to cradle him in one hand, the gigantic monster of a woman lowered him down to her crotch level, aiming each of his dicks towards one of her vaginas. "Finally! Releasssssssse!"

Having a moment to think, John believed it was time for himself to make another change.