The old centaur looked around in alarm. "Best find him quick, then! There are many dangers in this barn, especially for a child who likes to get personal with animals. Many of them here will get personal right back, and your brother will end up a beast himself!"
"What!?" Ryan was not sure he believed the danger, but since he was talking to a centaur, he was not going to argue. "Johnny! Where are you? Don't touch anything!"
"I'm over here!" They followed the child's voice to another stall, where they found the child standing behind a large, shaggy draft horse mare. He had his back to them, bare chested, with his shirt on the straw beside him. Ryan saw that the boy's right hand and arm were slick with fluid up to the elbow.
"Johnny! What did you do?" He started to move into the stall, but the centaur grabbed his shoulder and stopped him.
Johnny sounded distracted when he replied, almost like he was talking in his sleep. "I came in to see the horse, and she lifted her tail and winked at me with the funny black mouth under her butt. It was wet looking, and I felt it. She liked that, so I pushed my hand in, and then slid half my arm in. It felt all hot and slick, and I pulled my arm out. Then she sent a rope out and tied me to her. It feels really good."
"A rope?" That confused Ryan. "What are you talking about?" He tried to pull free of the centaur's powerful grip, but the old man said "It is too late already. Look!"
At that moment Johnny turned to face them and Ryan gasped. A slick, white ropey tentacle stretched from his belly back around into the mare's cunt, with soft-looking chestnut fur spreading out over the child's stomach. Johnny smiled sleepily at him, and Ryan gaped at the large brown foal's eyes that were no set in his brother's head. "I feel so good. She is my new mommy, and she is going to take care of me."
Even as Ryan watched in shock, the umbilical pulsed and his brother shrank visibly. His face distorted slightly, nose and mouth pushing out. Behind the boy, the mare's black cunt seemed to stretch.
"No!" This time Ryan tore free and ran to his little brother, gathering him up in his arms. Johnny felt slick and strange, almost hot.
"Let him go, boy!" The centaur shouted. "He is already too far gone - interrupt and you will have a half-formed unborn colt laying dead on the ground. Quickly! Before the mare decides to bring you into her womb as well!"
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