It was the typical S Mart employee screwup,Bob the Stock boy had got the two costumes
mixed up and you were now wearing a dragoness costume.
It was only now that it was too late that you realized the dragoness costume
was all streetched and torn because the previous inhabitant of it had gotten
bigger before no longer needing a dragoness costume,or for that matter,any
reptillian costume anymore.
Your body swelled and grew,your neck lengthened,your head reshaped,your
hind legs swelled and burst out of the costumes tattered leggings and
your body and mind reformed into that of a blue scaled dragoness.
Your belly began to swell as you became with child and you gave
birth to a slimy green goo gelatinous egg mass.
The wrecked costume slid off your huge frame and you stumbled out the room on all fours,took to wing
and flew off to join the other dragons.
Meanwhile a S Mart employee snuck into your wrecked room in a Haz Mat suit,
cleared away the goo and extracted a brand new scaly blue dragoness costume
from the gooy egg you'd laid...