The feelings Chip was getting from the monster horse cock was nearly overloading his brain, it was so sensitive and so large. His hips began thrusting as if on autopilot while his hands explored the gargantuan shaft. The cockbeast had full merged with his groin, horse blood started to flow back into his body and Chip began to feel every inch of the over-sized horse cock, sheathe, and balls as his own.
Soon the pleasure was just too much as he collapsed forward onto his new equipment, still trusting and groping his new cock, he began to lick the monstrous phallus and withering on top of it. His self stimulation reached its peak and he whinnied into his cockflesh and erupted inside of the tent with gallons of cum. With each blast his colossal organ began to shrink. The horse blood began to affect his slim 16 year old body as well. Every blast from his cum cannon was a surge of muscle into his lanky teenage frame, toning and shaping and pumping. Soon enough his shaft was near two foot long, short enough for Chip to try and fit his flared shaft into his mouth, but it was still too large and he mouthed and tongued his flat top and oozing hole, drinking in that rich, musky flavor. Chip had grown two foot to top out at a solid 7' and was built like an armature bodybuilder. He kept suckling his new horse cock, brushing his long brown hair back out of the way to marvel and his enormous body, seemingly human save his crotch.
The sea of cum from the reduced cockbeast flowed out of the tent to saturate the ground outside, sending a subtle scent into the night's air. The three other cockbeast, even more turned on with the show slowly worked their ponderous way out of the saturated tent.