"Daaaaaavid - yoOOOOHAAAWWWve a …TAIL TOOO HAAAA HEEEE HAAWWW!" was all he could shout in his earsplitting deep voice.
David pulled his pants up - and started to run. Ben was rooted to the spot in fright. He felt his own butt - no changes. Would he change soon? The floorboards were creaking as Jeff's body gained weight - his arms were forelegs, what was left of his shirt tore as his shoulders became more bulky.
David's ears sprouted into donkeyhood like an explosion -sending him to the floor in pain. He was growing gray hair on his cheeks, tickling told him it was coming in all over his body.
Jeff rolled around on his back, then with great effort go onto all fours. His arms were long enough to hold him on all fours now. He tried to stand; his huge body nearly that of a donkey. His face pushing into a vile muzzle - with pronounced goofy teeth, and large rubbery lips. He reared, trying to stand on two legs again - but he was almost and animal - he couldn't balance and with a loud CLOP his hooves hit the ground sending him onto all fours. "HEEEEHAWWWWW" he brayed, his ears flat against his head. His shirt tore and fell around his forelegs.