Jeff hadn't really considered the consequences of masturbation here. After all, he was outdoors in the wilds, in a prehistoric age where social niceties hadn't been invented yet. He didn't think it would matter that he'd fall asleep with cum on his chest, other than having to wash it off later.
But if Jeff had dug into Jahff's memories more, he would have realized his error. Masturbation was hardly unknown in this new era. After all, plenty of males aren't strong enough to win a mate in a world where competition could be fierce and they had to relieve sexual tension and stress somehow. While the new sapient anthros weren't too modest, they knew better to masturbate in public or at the very least not where they dwelt. Because dinosaurs had a strong smell and would draw the attention of anything passing by. Furthermore, painting oneself with your own seed was considered an open sign that you are currently single but seeking a mate.
Now, if had been another male tyrannosaurus who picked up Jahff's scent, they would had most likely rushed Jahff to run him off if not kill him. A few might have taken Jahff's 'invitation' and have sex with him, after establishing their dominance over him, of course. So it was very fortunate for Jeff that it was a female tyrannosaurus that picked up his scent.
However, this female wasn't a sapient anthro. This was a feral tyrannosaurus. She was pretty young though, at least in comparison. By saurian standards, she had just reached sexual maturity, though she still had some growing to go. Currently, she was in her first breeding season and was looking for a mate. She knew where there were large males, but wanted something small, something she could establish dominance over. She might be a virgin, but she didn't want to raise her tail for just anyone.
As such, she was very interested when she picked up the scent of a male. She followed the scent, soon picking up smaller nuances. This wasn't just the scent of a male tyrannosaurus, it was one of the changed ones, who had become smaller and yet smarter. But that didn't matter to the female. The sapients and ferals are still capable of mating with each other. The clutches laid were equally capable of hatching out offspring that can take after either parent. Though the sapient parent was only interested in raising the sapient offspring and vice versa. As a matter of fact, this enticed the female even more. A smaller sapient could easily be dominated. She wanted to be the one on top when she was mating.
The female soon found Jeff's campsite, with Jeff sleeping close to the red flower these sapients have created. The female paid no attention to the red flower. As long as she didn't touch its flickering petals, it would not burn her. Anyways, she was more interested in the male. He turned out even better than she expected. This male might be smaller than her, but she could see that he was very muscular and strong, good qualities to pass to her offspring. She might even keep the sapient offspring, just like she'll keep their father. A smaller tyrannosaurus like this would be the perfect mate to be dominate over.
She approached the male and sniffed him over. She could smell the seed covering his chest, proclaiming him as ready to mate. She started licking up the seed, it tasted virile and potent. Her tongue continued down the male's chest before coming to to his equipment. He was pretty large for a sapient, though the sapients had to be large in order to mate with both other sapients and ferals. She started licking at his balls and dick to determine their size. As his rod hardened, she was finding it to be an exceptional size.
Of course, Jeff was bound to notice this. He was still asleep when the female had started licking him. He had been dreaming about another world he could have created, a world of anthro dogs. He dreamed he was in a park, playing with a pack of puppies. The puppies had been licking at this face before one of them started licking his chest. The dream started taking a more erotic tone as the puppy's licking intensified. As she went further down, she became older and more obviously female. By the time she got to his waist, she was a grown woman with a curvaceous body and huge tits. She then started licking over his balls and dick, giving Jeff a lustful look.
But then Jeff's body told him him that he wasn't just having a wet dream. His balls and dicks really were being licked. The outside stimulus soon woke Jeff up. His sleep-hazed brain soon recalled that he was not in a dog park, but a prehistoric jungle. Looking down, he saw his dick was not being licked by a busty dog girl, but by a T-Rex!
Having one's most sensitive body part in the mouth of the biggest predator to walk the Earth was enough to wake up anyone instantly. Jeff's first instinct was to scream, but Jahff's personality seized control in his sleep-addled state. Instead, Jahff roared at the feral, sounding no less impressive from coming from a smaller source. The feral ceased its licking and roared back at Jahff, its roar one of defiance and challenge. It then lifted a foot and placed it squarely on Jahff's chest.
Jahff's nose filled him in on the situation. This was a female feral, smelling like she was ready to mate. From this angle beneath her, Jahff could see her cloaca, glistening with anticipation. Jahff actually found the idea agreeable, but there was just one problem: Jahff wasn't about to be the submissive one. If this female wanted to be dominant, she was going to have to work for it. With that, Jahff used his claws on her legs. The female removed her foot with a yowl of pain. Jahff quickly got out from under her and rolled away before getting up to take a good look at her.
As a feral, she was bigger than Jahff, but not as big as ferals could get. She also was lacking in scars that tyrannosaurs typically acquire over the course of their brutal lives. Jahff could see she was young, untested, unclaimed. That made her even more interesting to him. Neither tyrannosaurs wanted to seriously injure the other. They were both interested in mating, but neither wanted to submit to the other. This was a battle for sexual dominance to determine who was superior. The female had the advantage of being bigger and stronger, though she had a smaller, less experienced brain and tiny forelimbs of limited use. Jahff had the advantage of being smarter, more experienced, and having versatile, muscular arms. He also had the disadvantage of relatively smaller size and fighting with an erection. Jahff liked those odds.
The female moved first, swinging her tail at Jahff. Jahff ducked under her tail before giving it a passing slash. The gashes weren't too deep, but they bled and stung, a more savage version of a paper cut. Jahff got inside her reach before giving a hard thump with his fist to her hip. He held back so it wouldn't break. She was going to be needing it later. The female roared before swinging her head at Jahff. Jahff allowed her to connect, because it gave him the opening he needed. He grabbed her throat with both arms, a feat impossible for a human but as a sapient, Jahff was able to get his arms around. The female tried to shake him off, but Jahff swung himself up. There was a brief, eye-watering moment of pain when his erect dick collided with the female's neck. A lesser sapient would have fallen off and curled into a ball. Jahff just wrapped his powerful legs around the female's neck and started squeezing.
The female's shaking became a little more desperate as her breathing was constricted. But Jahff managed to hold remarkably well. It was like riding a bucking bronco, except most people wouldn't be riding one just to mate with it. The female's neck wasn't comfortable, especially with his dick pressed up right against it. But Jahff was persistent. His memories told him this strategy has worked successfully before. Though other times it was against male ferals to drive them off.
The female's struggles became weaker as her air supply diminished. Finally, she stopped thrashing altogether. She wasn't unconscious yet, but she knew she had been beaten. Jahff released his grip and slid off of her. The female gave Jahff another look before turned around. She crouched down to the ground and lifted her tail. Jahff grinned to himself. He was the victor, now to claim the spoils. His dick took a bit of a beating, but it was still hard and raring to go. He pushed the female's tail higher while he angled his dick at her cloaca. It would be an awkward position, but it would be worth it. Once he was lined up, he started spearing her. The female growled as she felt herself being stretched open for the first time. Jahff was thrilled to be claiming virgin meat. As soon as the female was used to the new presence in her, he began his thrusting.
Jahff gloried in the feeling of mating this fine beast. He had been with other sapients before, left their wombs swollen with his eggs. But this young female was a rare treat. Ferals rarely mate with sapients until they're more seasoned and more interested in producing more eggs before they get too old. It was about halfway through this mating that Jeff's personality awoke fully. He had let Jahff take the driver's seat to deal with this situation, relying on his savage experience. But now Jeff was becoming more aware of what he was doing. He was fucking a dinosaur! Not just any dinosaur, he was fucking a T-Rex! He had a feeling he was living somebody's perverted fantasy right now, but was it his? He had to admit he was enjoying himself, but he was basically having sex with an animal. Sure, he was half-animal himself, but was this too far? On the other hand, Jeff was very close to finishing. And this female would be extremely irate if he pulled out before she was finished. But at that point, there was no time for second thoughts. Jeff and the female let out roars as they climaxed, Jeff shooting a thick load of seed deep into her.
Jahff could probably go for another round, but Jeff was feeling tired. The fight and the mating took a lot of energy and he hadn't had a full night's rest yet. He pulled out of the female, his dick still dripping a little. He was expecting the female to go on her way now that she had his seed. Instead, she just lied down where she was, just far enough from the fire. Jeff decided to lie down next to her. The female didn't growl at him or push him away. She was certainly more comfortable to lie against than the ground. Jeff soon drifted off to sleep, wondering what he and his new companion will do in the morning.