The image you'd falled asleep looking at, an enormous Western Dragon with a round belly sitting in a nest of near-molten rock and gold, with a pile of precious eggs jealously guarded. You shudder in pain and try once more to stand, wobbling unsteadily as you clutch onto the book and a nearby shelf for stability. You feel hot, your skin flushing and burning as you stagger through the stacks of shelves back towards a half remembered entrance. You shudder and stumble, feeling a rumbling in your belly and your balance being thrown off. As you near the glass doors you feel a pain in your hips where your pants seem to be digging into your grumbling stomach. A wave of nausea meets the pain in your head as you look at the faint reflection in the glass, the faint glimmers of light around your face and the way you hunch over, your clothes tight and suffocating, traces of something like smoke trailing you as you stagger out the door.
You trip and fall onto the grass outside the library, the book sliding away from you as you let out a loud groan, pain lancing through your belly and spine. You let out a groan that turns into a growl, thick strands of drool and spittle escaping from your mouth as it struggles to fit around your teeth. You feel the aching in your belly throbbing and redoubling, feel the collar of your tee-shirt digging into your throat and choking you. Your hands raise to grab at it and your nails scrape harsh over your skin and through the fabric, shredding it and letting your breath rush back in. Your feet ache as they scrabble for purchase in the turf, your shoes straining and then splitting with a loud rip as your clawed toes dig into the soil.
A coughing whine of surprises and pain escapes your throat and growing muzzle as your feet and claws grow larger, digging trenches as wide as your wrist into the turf, growing to support the rest of your swelling body as the clothes you wear burst and shred around patchy dry skin that swells and twists. Your spine arches and aches and you feel something lashing behind you, first stubby, but growing longer and covered in spikes as it does. Your hands dig into the turf, forelimbed claws now swimming before your eyes, long and vicious claws protruding from black scaled talons. Your neck, thicker, longer, growing spikes that glow dull ember-red along its lengths, bends to look down over your form. Your mind still swims, unable to put into words what it is seeing as your back aches, new wings beating fitfully. Your roll onto your side and shudder with strain as your belly continues to grow and distend, swelling outward from a reptilian trunk into a bulbous and gravid gut the size of a minivan.
Your eyelids flicker, first one set, then another translucent set that protects you from a gust of hot smoke and cinders from your maw as you see that you have, between powerful scaled legs, another change. You didn't even feel it or notice it, but now you see a dripping and drooling sex, female and seeming to pulse and gasp in the cold night air. Like the spines decorating much of your black scaled body it glows dully red and you can feel the pulsing heat from it. You struggle to all fours, seeing the book nearby, and though there is no mirror near, you nonetheless know what you have become. A pregnant ash dragon bigger than a city bus, your mind racing in panic as the pain settles to a dull discomfort from your womb and you struggle to find your bearings and decide to...