Ruben's bushy tail brushed against his legs.
It was kind off hard to keep his balance on hooves, seeing as his legs were still the same shape as usual and were not designed for this kind off flat fleet.
But of course, the only thing he could focus at was obvious.
His giant horse cock, erect from his sheath, leaking with pre.
Ruben was in awe with his cock, quickly giving it a test pump.
The boy instantly went weak at the knees at the sheer sensitivity of the movement, writhing in pleasure.
He understood now, why Max called it a great choice!
Ruben knew right then and there, what he was about to do.
He quickly looked around and something caught his eye.
On the back wall there was a chute with a little sign, "Sample Delivery", next to it stood a little drawer.
Ruben noticed it earlier as well, but was too distracted by the first time meeting Max to spend any attention towards it.
He opened the drawer, inside it were these weird looking cups. Ruben picked one up and examined it.
Then it hit him. These were sample cups! There was a label on it that indicated its use for the breeding program.
Ruben took off the lid of the cup, and set it on the dresser.
He took his enormous horse cock in his hands and started thrusting.
His legs bucked under the sheer feeling of his hands touching the sensitive skin of his equine member.
His giant balls dangling back and forth, as Ruben kept going, huffing and panting.
Ruben kept pumping, overwhelmed by pleasure that spread throughout his entire body, even radiating in his tail, causing him to swish it everywhere.
His ears twitched on the top of his head.
Ruben closed his eyes, his imagination and horniness filling his mind with vision of mares and stallions.
His body still writhing in pleasure, as he envisioned himself further, he saw a mare, and mounted her, his horse cock set inside its giant horse pussy, thrusting back and forth, neighing and whinnying.
It didn't take long anymore, as Ruben felt a pressure building up, rising towards the tip of his cock.
He quickly snapped out of the vision fast enough to snatch the cup and stick it on the tip of his horse cock.
And with the most powerful sensation Ruben has ever felt, his equine member launched a wave of horse cum, forcing Ruben's knees to cave, as he dropped to the floor, with a powerful bray.
Ruben sat on his knees, cum still dripping down from his cock into the cup.
With some self discipline, he finally managed to get himself off of the ground. His horse cock stopped leaking and returned in his sheath.
His knees were still wobbly from the experience, he could still feel the pleasure in his gut.
Ruben grabbed the lid, and put it on the cup, then with one fluent motion, put the cup through the hatch, delivering a fresh new batch of horse semen.
Ruben walked towards the kitchen counter, wobbling on his hooves, as he opened a drawer, and quickly popped a pill.
It didn't take long before Ruben reverted to a normal naked human teenage boy.
"That was awesome!" He said out loud, as he crashed on his couch, still very much butt naked.
"So what should I do now?" he asked himself.