Turning you into a dragon monster girl would be pretty fun.
Like a long con thing, like magic gauntlets, made from a red dragon, with claws made straight from the dragon. Probably should have explained the curse of what happens if you wear dragon scales without checking with a wizard but I mean, what's the worst that could happen?
How you can't take it off cause it has great stats, how the days go by and it's easier and easier to use, like it's becoming part of you. The scales spreading up your skin, you think an allergic reaction at first but it's not, but the gauntlets call for you, it feels wrong to not have them on. Until one morning you wake up and forget to take them off the previous night, but finding them, no, finding yourself with scales lining your arms, your hand with black claws, with scales spreading more towards your back. Trying to stop it, drinking a counter potion but making it worse as you feel yourself change more and more. Feeling as you reshape and grow, your clothes and armor barely being able to hold you together as the scales spread, as your body grows to a proper dragon size, one to instill fear. Your chest bursts out, cracking your armor and clothes into pieces, a remnant of your humanity, as softer scales grow around them, perfect to still be grabbed~
The rest of your armor doesn't fair better, you use your new claws and strength to rip apart the remaining pieces, as your leggings snap and crack, showing off more and more of the new you, as the scales spread more and more, but the scales reach your face, as you feel your face reshape, your horns coming in, your muzzle growing, everything changing as heat builds up, the cries of change let out in a burst of fire, as more change comes. Feeling your wings pop out your back, each throb another growth and growth, you can feel your mind breaking, not of pain but of pleasure, letting out another roar of fire as you spread your new wings, illuminating the sky with your beautiful flames. The finale is almost here, as you grab your ass for the new sensation, a providing pain in your rear as your tail pops out, sending another wave of pleasure as it flops down, falling in pleasure as the first of your dragon orgasmic.
There you stand, in the remnants of your armor, torn to shreds, 10 feet tall, wings spread out, your tail loving with joy, as you explore your new body. Quite the figure, curves to make any adventurer think twice, and even with scaled all around you're still soft in the places that matter, squeezing your new bust size with a moan and a flame escaping your mouth. But as you explored more you went to the white dragon in the room, your leaking pussy, and one touch sent you into overdrive.
Your fingers not enough, your mind quickly filling with the need to mate, begging, your party members finally arriving to hear the commotion, only finding a dragon girl, begging for relief, no, demanding it as it pins them and kisses them, leaving scales on them as well...
Feeling as their once regular dick turns into a dragons knot, the warmth growing hotter and hotter, hearing the moans from other members as they try to resist the changes, holding on to each other, trying to fight back but falling into the lust themselves as they change, ripping off their armor to freely let the change happen. You felt as if you got filled for the first time, a hot mess filling you deeply, as another mate grabbed you, another poor soul still needing to finish the process. Hours and hours, your once noble party of heroes turned into nothing but a mindless horde of dragons, breeding, and breeding, lost in lust. But in the end, you were left, that last one not passed out from it all, an expanding belly as you felt the egg start to form, what you didn't expect was me coming along.
A simple collar would do, marking your once troublesome party as mine to control, and to further my plans. Soon I will have my own army of fearsome dragons at my disposal, but it'll take time, the time I may not have, so enjoy this spell darling, just this once, feeling as you rapidly swell with both eggs and milk, feeling as your first eggs comes out, one by one, a nice batch of 4, great for a first time. Now relax my pet, for tomorrow is another day of fun~