The lines of gray thick fur weren't subtle at all. For by that intense final thrust, the one which pooped your canine knot deep into jack, acted like a switch to transform both Jacks' and your own body. The gray fur lines kept trailing up both of you from groin to chest, spreading fur outwards and all over. A couple cracks were heard in your bones and joint, followed by your buddy Jack. While he himself moans like a gray wolf with his tongue hanging out in heat. What once stood two guys in costumes one minute ago, now stood two muscled wolves screwing each other doggy-style.
Though Mitch [your name from now on] had already pooped in his canine knot within Jack tight doggy pie-hole, the transformation forced his new muscle feral body to be in heat once again. Mitch's continued pounding Jack's plump muscled rear. Jack didn't stoped it but welcomed it with full on wolf feral embrace through panting and cheering.
"Keep at it Mitch!" Jack growled wolfishly. "Keep pounding me hard! More!" He continued between pants and canine drools.
"More?!", Mitch continued, "HELL YESH!".
From a standing position, Mitch, while still attached to Jack by his canine knot, took initiative as a feral wolf by a lunge. He jumped up and to land with his full weight as hard as he could over the bed. Amplifying his canine dick's thrust that threw Jack's in a satisfied lustful wolf moan! Then on Mitch clutched his thick muscled arms around jack's torso with his head tightly pressed next to Jack's own canine head. Both wolves were panting hard with wet sloopy tongues sticking out. One body kept pounding another with full steam to the point of arousing a second change. As Mitch Kept pounding Jack like a jackhammer, his body kept sinking further into Jack's own muscle wolf form. By each consistent powerful thrust, Mitch pulled out less and less of himself out. And more of his own fur stucked to Jack's Fur. Each forceful thrust, kept burying Mitchs' mass into jacks. As more mass was added to Jacks, his own form became more feral.
At the point both wolf's groins were locked in place like key to a lock, Both started to merge in waves of lustful corporal ecstasy. Mitch couldnt stop pounding Jack's muscled rear after they locked as one read end, rather he kept automatically punidng him and burring himself into jacks. From the mad heat, One body came out of this confusing mess, growing in muscle, still moaning in heat, standing on all fours like a true feral wolf. It stood 6'3'' tall on all fours covered in muscle in a reddish brown hue. Two canine rods hanging side by side under this Hound stretching 16 inches long and about 5 inches thick, matched with 2 pair of canine balls one over the other. The Hound stood up on all fours stretching two wolf heads with sets of black horns. Both formerly Mitch and Jack were still panting ridiculously hard as if they had just run some intense marathon. By instinct they walked in front of a full bodied mirror to see what sort of mess they got into this time.
"Wow, the hell?" Both Mitch and Jack said in unison out of their horned wolf heads. Then turned heads turned to each other, scanning their feral form.
"Nice horns Mith",
"You too bud," he smirked.
"We're hellhound by the look of it." Jack said in a deep baritone voice as he licked his sharp fangs.
"Hellhounds indeed," Mitched followed as he nibbled Jack's ear like a lover.
Then Jack's moved over to french kiss Mitch. The hellhound stood on its hinged legs for comfort while they made out with each other.