Early one morning, before sunrise, Mike was awakened by human hands. But they did not belong to Nia -- they were those of her brother, Arro. "Wake up, centaur," said the teen, "I've brought you your breakfast."
Arro pushed a basket of food toward Mike. "Uh, thanks," said Mike. He began to eat, while Arro watched him, the young man's face unreadable. As he was eating, Mike asked, "Is your sister well?"
Arro smiled strangely. "Father sent her to town to buy supplies. She should be back tomorrow."
"Ah," was Mike's only comment, as he finished his food. After eating, Mike thanked Arro for breakfast, and walked over to where the equipment was. With only minimal effort from his huge muscles, Mike hoisted the plough over his shoulder. He turned, and was surprised to see Arro watching him intently, a look of hunger on his face. The look was quickly gone though, and Arro picked up the food basket, and opened the door for Mike. As Mike carried the plough out to the fields, he wondered what it was that Arro was hiding. Mike harnessed the plough to himself, and began to pull it through the earth.
At noon, Arro came again with food, and his father came along. The farmer was not too drunk, and able to stand without toppling. "I see you're almost done, centaur," the farmer said, "That's good. Once Nia is back with the seed I sent her to buy, we can start planting these last fields as well." The farmer stomped off after that, leaving Arro with Mike. Lunch passed quickly, and in silence. When he was finished, Mike once again began to pull the plough through the earth. Arro watched him for several minutes, and then left.
At dusk, Mike carried the plough back to the barn, and put it in its place. He lay down, to catch some rest before supper came. He was quickly asleep and so remained, until he felt hands squeezing his shoulders. His eyes opened, and he saw that those hands belonged to Arro. "I have your supper, centaur," the young man said, pointing to a basket. Mike devoured his dinner ravenously, hungry from the day's hard work. Arro watched him the whole time, his face unreadable. When Mike was finished, he thanked Arro.
Arro blushed slightly. "Centaur," he said, his voice somewhat nervous, "there's one more thing that my sister does for you..."
Mike looked at Arro, not entirely sure what the human meant, and worried about what he might know. Mike's fears were confirmed, when Arro began removing his clothing. "Arro, there's no need..." Mike said.
Mike was cut off. "I've seen you and Nia," Arro said, "I've seen you fuck her with that big tool of yours." Mike blushed a little. "I want what you give her. I want that big cock, centaur." Arro was completely nude now, his young body surprisingly athletic. "Stand up," he commanded. Mike complied. "Now show me those big muscles," Arro ordered, a lecherous grin on his face. Mike of course complied, flexing one bulging muscle after the next, for Arro to touch and admire. When Mike was finished, Arro fell to the ground, and crawled underneath the big centaur. "Get hard for me, centaur!" he gasped, "Get that horsecock up!"
Mike's big rod rose, becoming hard and thick. Arro devoured it, forcing the big head into his mouth, trying to take as much of the shaft as he could. Although Arro could only get about half the length of Mike's extra-large dick into his mouth, he worked as hard as he could on that half, while his hands played with the rest of Mike's shaft, and with the big balls as well. Despite himself, Mike enjoyed Arro's attentions; the teen was a gifted cocksuker. With a groan of pleasure, Mike shot his hot load down the hungry farmboy's throat; Arro eagerly drank it all. As Mike finished, Arro continued to suck, desperate to make sure that every precious drop was his. At last the teen pulled off, a smile on his face, despite how far his lips had had to stretch to accommodate Mike's girth.
"Most excellent, Mr. Centaur," Arro cooed, "your cock is most impressive, and your cum is quite delicious!" Mike couldn't help but smile at the compliments. "Now, I want you to fuck me up the ass!" Mike protested, "I'm too big, I'll rip you apart!" even as the magic of Arro's command forced him to move into position, his cockhead at the farmlad's rear entrance. "Not to worry," Arro said, "I've been preparing for this ever since I first saw you! My ass can take that huge dick of yours and then some!" As Mike pushed in, he found that it was true - Arro's ass was surprisingly elastic, giving way to large pole that invaded it. Arro moaned with desire and whispered encouragements, as Mike continued his inexorable advance.
"Don't cum yet," Arro breathed, "not yet." Mike felt his balls tighten at this, but could do nothing. "I don't want you to cum in me until you have plenty of spunk," Arro explained, "so just keep fucking me, until you're completely full again. Then you can cum, and then you can stop." Mike's eyes widened at this. "It- it could take hours!" he gasped. "Then I order you to make cum faster!" Arro sneered, "I'm not letting this end unless it's with a full load!"
Mike felt his balls churn strangely, and seem to tingle. His cum production was increasing - he could feel it. "Your wish is my command, master," Mike joked. "Then I wish you'd go as deep as you can into me!" Arro breathed. With a grunt, Mike's muscled body drove his horsedick into Arro as far as it would go, producing a strangled cry from the farmboy. "Is that not what you wanted?" Mike asked, a trifle smug, as he continued to pound Arro's ass. "C- continue!" Arro managed, "Keep fucking me, and don't cum until you're full. And then, don't stop until you've gotten every last bit out!"
And so, for the next hour, Mike fucked Arro. His muscled body was already tired from the day's labors, but the magic saddle compelled him, and provided him with energy. He would fuck until he keeled over, if those were his orders. Mike could tell that Arro was exhausted as well, and undoubtedly quite sore from the way that his ass was being treated, but Mike could not stop fucking him, and Arro asked for nothing different.
At last, Mike's balls were full of cum, and he told Arro as much. The farmlad perked up at this, and began to giggle. "I- I'm cumming!" Mike groaned, as his dick was finally able to unload its cargo into Arro's tight ass. "Yes, yes, YES!" Arro cried out, "Give me every bit of it, centaur! Shoot that powercum into me!" Mike of course complied, and continued to pound away at Arro's backside, until every drop had been wrung from his dick. Finally, Mike pulled out, and sunk to the floor, utterly exhausted. Arro was on the floor as well, his butt red from abuse, centaur cum leaking from within. He had a madman's smile on his face though, and his eyes were wide with excitement.