Please read from the beginning: http://www.furaffinity.net/view/1295601/

Joe used horse shampoo
By Picklejuice

Joe smiled as he walked down the street. The Mane and Tail horse shampoo he picked up by accident was working really well. He felt some tingles from his head travelling down his spine to the base, and felt good.

As Joe was doing some window shopping, he felt his pants getting tighter. He looked down and felt at his jeans to see what was wrong. He doubled over suddenly, and the strangest sensation enveloped his body.

He grew a long horse's tail.

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What happens next?

Joe finishes changing: http://www.furaffinity.net/view/1295630/

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Suggestions for the next pic are welcome. To guarantee your branch is illustrated, send $5 to picklejuice_13[at]yahoo.com on paypal.