Derrick felt dazed, having trouble concentrating, but it did not matter. He simply nodded in agreement with stunning blonde incubus, and let himself be guided back up on the massage table. The regular masseuse giggled and left, shutting the curtain behind her.
"Now then." The incubus gave him a dazzling grin. "My name is Vetis. I specialize in the corruption of youth. Let's see if we can get rid of some of those pesky morals."
Derrick heard the incubus speak, but he was still too mesmerized. His eyes kept drifting to the enormous bestial cock and balls, and then back to the glowing red eyes and magnificent horns.
Vetis took note and chuckled. "So, let's work this out in trade. How would you like to have sexual equipment like mine? All I ask in return is your sexual taboos. They would just get in the way of enjoying yourself."
"Uh, OK." Derrick wasn't really clear on what that meant, but enjoying himself seemed like a great thing. The incubus began massaging Derrick's crotch, but did it from the end of the massage table so that he was leaning over with Derrick's head pressed into his crotch. The boy could not see Vetis' huge cock start to slip ghostlike into the top of his skull, but he did feel a strange pressure and heat that began to build. The sensations from his own crotch were also getting more intense as the incubus' fingers stretched and molded.
Vetis grunted in pleasure as his demon cock thrust magically through hair, scalp, and bone to penetrate deep into Derrick's head. 'Fucking with his brain' was not just an expression for demons, and as the incubus began to rock back and forth, the demonic forces scrubbed away all of the 'rules' Derrick had learned growing up, removing all sense of right and wrong concerning sexual acts. At the same time, Vetis' hands were busy giving the boy far more substantial and no longer human sexual parts. Since size was always an attraction, he pulled and prodded the boy's average human organs longer, thicker, heavier. Veins grew pronounced, and a heavy sheath formed at the base.
Derrick was overwhelmed by powerful sensations of lust and pleasure, the demon somehow giving him orgasms in his head and crotch at the same time. His hands dropped to his own organ and he gasped at the thickness and heat. The incubus did not mind his hands, sometimes pulling them up against his expanding cock and heavy sheath with the rubbing.
Derrick had a horse cock now, still human skinned but unmistakably animal. As Vetis built to his own orgasm within Derrick's brain, he expanded the testicles, choosing to give the boy the low-hanging sack of a bull. He would never have human children, but should he find a female of any species willing to mate with him, he would produce monstrous offspring. The incubus was slamming hard against the top of Derrick's skull, and it began to flatten slightly. Spurts of demonic seed began to release, becoming solid as it left the spirit penis. Derrick felt the cum as hot blasts of pleasure.
The incubus' deft fingers completed the huge, bestial sexual parts and slipped under Derrick's butt to rub against his anus. The tight hole loosened, then got slick as it became something more like a huge equine cunt. As he pulled slimy fingers free, Vetris gasped and grunted as he erupted inside Derrick's brain at the same time the boy's new cock and balls turned black and then shot forth a jet of bull semen that rained down on them.
Derrick screamed a hoarse, bellowing cry as pleasure and lust exploded through his entire body. He was consumed by orgasms that left him shaken and weak ont he table, sweat dripping form his body. Vetris pulled his throbbing cock out of the boy's had, leaving no indication of any opening he might have used. However, demon jizz now filled every nook and cranny of the boy's skull, creating a powerful sexual drive and burning need for sex.
When Derrick finally sat up, he stared at the massive sexual equipment he now had - his heavy black testicles swung below his knees like softballs in a black sack. His equally black sheath and cock were sized for a draft horse, and his flat-headed, thickly-veined penis nearly touched the floor soft, and would be level with his mouth when erect. Reaching back, he felt the sensitive, slick opening of his anus.
Vetris grinned and tousled the boy's hair, which was much coarser now and covering a flatter, thicker skull. Derrick's features were still recognizable, but he looked very bestial now. So much so that he gave a very strong impression of being a powerful bull or work horse. He also gave off very powerful pheromones that would attract and females of all ages.
Vetris said "Well, that's good for now. Go out and have fun."
Derrick gave the incubus an open-mouth grin, drooling a little as he shuffled out fo the spa. He needed to find something, someone to have sex with. A minotaur, a woman, a cow, a tree.. .