Deciding, Mary grasped the vial showing the Male symbol. She didn't want to fully become an animal, but obviously these vials really worked, and she was excited at the thought of experiencing a full change from her natural (boring) state. She was so tired of seeing herself in the mirror each day, and now she could finally glimpse what it would be like if she'd been born differently! With an confidence she normally lacked, Mary tipped back the entire vial, assuring herself that at least she'd still have hands to use to return herself to "normal"... that is, if she wanted to ...
Replacing the vial, Mary jumped to her feet just as tingles raced throughout her body. Curiously, she seemed to be standing only on the balls of her feet now; glancing down, she realized that her feet had changed further, now almost completely resembling canine paws with four short, stubby toes and a useless dewclaw dangling beside what had been the arch of each foot. It felt very uncomfortable when she tried to lower her former heels to the ground, so she remained balancing on her new paws instead.
Just then, the tingling centered in her groin, and Mary padded quickly to the bathroom, removing her clothes on the way. As she got down to her panties, she was shocked to see a rather large bulge beneath the fabric already! As her fingers grazed it through the thin material, a wave of pleasure washed over her, causing her to press more firmly against this new part of her anatomy. Mary firmly rubbed it for a few more seconds, feeling it grow firmer and larger with each pass. Curiosity overcoming her, she grasped the edges of her panties in each hand and quickly lowered them, surprised despite herself to see an erect, six-inch penis sprouting from her groin! Raising one hand back up, she felt a loose sac just below her new cock, but as she held it, two firm, grape-sized testes dropped into it, completing her male genitalia.
"Holy shit!" Mary thought. "This is INSANE." She lifted her gaze to the mirror just in time to watch her waist widen, matching the width of her hips. Her shoulders were a little broader, seeming to still be growing as muscle developed over her chest, her smallish breasts flattening and firming into decent pectorals as more muscle wrapped up and around her neck. Focusing on her face, Mary watched as her features enlarged, her jawline growing more pronounced and her brows pushed forward slightly, shadowing her eyes.
She squinted, wondering about the smudge on the tip of her nose, but as she leaned closer to the mirror she realized that the texture of her nose had changed, darkening and tipping upwards. A light growth of beard rapidly began to push out over her chin and jaw, but it didn't stop there - before she could blink, her entire face was covered in short brown hairs! Twisting this way and that, Mary couldn't see a single bit of un-furred skin from her hairline to her neck!
Struggling not to panic, Mary gasped internally. "The Male Vial must be accelerating the Dog Vial's effects along with its own!" At this point, she could only watch and wait to see how far the changes would go!