Ian finally makes it back to the house as the storm slowly ends. He had started feeling horny again but knew that he needed to keep from acting on the feeling.
Walking up the drive, he sees his dad’s truck parked with Jose’s trailer. He didn’t see Jose’s truck and the only person he saw was inside the truck cab. Walking up he soon sees that it is Derek inside and the truck was bouncing.
“No, please. No” Ian says as he runs up and open’s the truck door.
Opening the door confirmed his fears. Derek was inside with his zipper down and cock out. Derek was flapping away to his now sixteen-inch penis. As Ian watch his brother’s hands go up and down, Derek moans and groans in pleasure as the penis stretches out two more inches, his penis darkening to a light brown and his balls growing and darkening as well. The penis head flatten out and Ian could hear leather starching from Derek’s balls.
“Derek stop! Can’t you see that you are changing.” Ian yells.
Derek shakes his head as he closes his eyes as his pleasure grew. “Feels…. So… Good…. Need… Release.” Derek spook between moans. As Derek continued, his muscles start growing faster, constricting his clothes. “Oh…” Derek kicks out one of his feet outside the truck cab as his shoes starts inflating. Soon, Ian sees what looks like a hoof burst out of both shoes as Derek’s skin starts darkening and brown fur grows in.
Derek’s calves and thighs grow massive as Derek’s hips and butt start causing rips in his shorts. His chest pushes out as his arms gain mass, taring the sleeves off his shirt and rips the back of it. His ears become pointed as his face pushes out.
Ian could see his brother becoming more and more like a… horse. “Derek stop. You are becoming a horse. You must stop and fight it!”
Derek shakes his head again as if he was in a dream and Ian’s words were pulling him back. “Ian?” Derek says before another wave of pleasure comes over him. His boy grows larger, ripping his clothes off completely. His hair grows into a mane as his head and face comes more horse like. Derek’s hands thicken as his nails turn black and fur covering the last of his skin. A tail growing in behind him and wiping around the seat.
Then Ian hears the leather sound again as Derek’s balls and cock start growing again in Derek’s larger hands. The penis pushes to twenty inches before jumping to twenty-four. Derek lets out an inhuman scream of pleasure as he starts cumming inside the truck.
“Derek!” Ian screams again.
This time, Derek wakes up mid-cum. “What?” he says from his horse lips. He looks at his hands as his penis continues to cum to the other side of the truck. “Ian? Help me.” He says before he grabs ahold of his penis again. Restarting his pumping.
“Derek… no.” Ian says, tears in his eyes at the horse man returns to his changes.
Then Ian hers a woosh in the air before seeing a dart hitting Derek in the arm. “What?” Derek says before going limp in the seat.
An older Scottish man walks up behind Ian. “Grab his legs, lad. We got to get him over the property line. You too.”
Ian doesn’t think and does as the man says. They both grab a leg of the massive horse man and pull him out of the truck. Derek’s body hits the grown with a loud smack before the two continue to pull him to the old man’s truck at the gate of the land. As they pass through the gate, Ian feels an energy leave his body and Derek’s body stops growing.
The pull Derek to the bed of the truck before Sasha jumps out of the cab and runs up to hug Ian. “You are alright.” She says.
“I am. But who is this?” Ian asks.
“This is my father.” Sasha says.
“You can call me Malcolm.” The old man says. “And we have a lot to talk about with you and my daughter. But first, is there anyone else on the land?”
“I don’t know, Sir.” Ian says. “I just came up on my brother and haven’t seen my parents.” Ian starts to head back to the house when Malcolm stops him.
“I’ll go lad.” Malcolm says. “Don’t need you changing like your brother.”
Ian looks down at his brother as Malcolm runs to the house. Derek now looked like a horse man. He was easily eight feet tall and over three hundred pounds. His body was shaped mostly human, minus his hoof feet and horse head, his mane was messy from the dragging. Fur covered his body and the now limp cock gently laid over his waistline, slightly smaller, to just besides his chest.
“This could have been us.” Sasha says to Ian.
“But it is now my brother.” Ian replies back.