Great job done by  witchfiend . Here they begin to be effected by the islands nefarious curse, their inner beasts rising to the surface, as well as progressing their age from Human years to Donkey years which for arguments sake is about 2x human years.
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It had been the best night of either of their young lives. Rides, food, fireworks, the island had it all and they let you do anything you wanted to; even freely ripping apart a mansion on the island. It was incredibly cathartic for Amelia as she did what she wished she could have done as a maid.
While she wreaked havoc, shattering vases and knocking over full book shelves, Arthur's heart was lit aflame. Amelia's genuine happiness and beautiful smile was like Cupids arrow to his heart, and at that moment he wanted nothing more than to make her always smile like she was right now (blocky teeth and all).
All that exertion wasn't completely without consequence. at some point in their escapades Amelia had busted a seam under her armpit. she had this dress for the better part of 2 years
"I must be outgrowing this faster than i thought" she spoke to herself as she noticed rip and the dress feeling a little more snug on her than usual.
The both of them were tired as well as feeling a little achey from all the running around they had been doing all night. they find an empty tavern still open on the quiet side of the Island.
Amelia wasnt the only one wit a wardrobe malfunction as Author discards his now constrictingly small jacket onto one of the near by bar before pouring Amelia and himself a mug of cold frothy beer with a bucktoothed smile.
they indulged in the beverage that was always out of reach for them. their 2nd mug sends a chill down their spine. They shivered slightly from the taste of the cold crisp beer, not noticing their hair begin to frizz. the more beer they took in the drunker they got and the more they developed. They both slowly grew bigger Arthur's body slowly broadening, while Amelia's developed curves that her dress was not quite designed for. The ties of her now small corset breaking free much to Amelia's relief . Catching a glimpse of themselves in the nearby mirror she Amelia noticed how unkempt her hair now looked something she would definitely be reprimanded for by her employer, but here they couldn't care less, even with their new streak of coarse hair growing down the back of their neck. They drank more than they could ever hope to afford back home as they winded down from the exciting day.
Now substantially intoxicated, they were blind for whats to come. with a tingle brought on by another sip of beer, Arthur's ears sprang up into long furry donkey ears, going unnoticed by Amelia; even after she sprouts her own set. the strange tingle left as quick as it came, leaving them with a matching set of foolish looking ears; one set grey, the other tan.
Like how she was too drunk and distracted with thoughts tomorrow , likewise Arthur's attention was also drawn away from her ears.
instead of looking up above her head, his eyes dove deep into the cleft of cleavage that now pushed out from Amelia's top, making his already small pants feel even tighter. To him she was at that moment the most beautiful thing in the world. Making his move, he gently wrapped his arm around her. and her response was to snuggle further into him, feeling comfortable and safe in his embrace. He didnt ever want to move his arm, even as it began to tingle, his fingers slowly going numb as they began to meld together just out of both of their sights.
Amelia happily took another drink, as she felt Arthur's strangely stiff hand caress her shoulder, with something hard and smooth brushing down her arm. It was good that they decided to find a place to settle down, She didnt intend to complain but Amelia's feet had been feeling sore for the past couple of minutes, now shimmying one of her feet out of her shoe to relieve her cramped toes.
Her shoes too small to acomidate changes that were beginning to befalling her feet, the same as they befell his hand. stiffening toes curling inward before fusing together inside her stockings, hardening, slowly turning into hooves like Arthur's.