Okay this came from the depths of strange and ended up here, actually rather adorable :P Enjoy! :)
"Hey, whose is this kitten?" Natsu called out into the guild hall, the kitten in question padded back and forth across the wooden table, following Natsu's finger. It's black fur was sleek and shiny, and it had large blue eyes, in addition it's paws were slightly too big for it's size making it stumble occasionally.
"No idea…" Mira replied as she passed the table.
"It's so cute!" Lucy cooed, "she picked it up, holding the up in front of creature up in front of her. It wriggled, the pads of it's paws pushing against her grip.
"Let it go Lucy," Erza rolled her eyes, "it obviously doesn't want to be held."
Pouting, Lucy plopped it back on the table, the kitten padded back over to Natsu mewing quietly, it dug it's head into the palm of Natsu's hand, purring contently.
"It seems to like you!" Wendy smiled, "I wonder if it has a name?"
"It's probably a stray so I suppose not." Natsu said with a small smile as the kitten rolled onto it's back as Natsu scratched it under it's chin. It continued to purr happily, closing it's eyes. Natsu then frowned, what's this, he noticed something on the kitten's chest.
"Has anyone seen Gray?" Juvia wandered over, "Juvia hasn't seen him today and is getting worried."
"No," Erza replied, "he hasn't gone out on a job has he Mira?"
"He's meant to get back today," she replied with a frown, "but I wouldn't worry."
"Juvia is worried," the blue haired woman frowned, "maybe Juvia should have gone with him on that job!"
"I'm sure he's fine," Wendy offered a smile, but it didn't seem to calm the Water-Mage.
"Hey guys! It has a weird light blue patch of fur on it's chest…" Natsu trailed off, "it looks slightly familiar…"
"Which side?" Erza asked.
"What do you mean?"
"Which side is the mark on?" She clarified.
"The right…" Natsu looked up at the group, then back at the kitten which had now rolled over and padded back to Natsu's hand.
"You don't think?" Lucy whispered in shock.
"No way!" Natsu let out a 'ha' of laughter, he picked up the kitten, holding it at eye level, it stared back, unblinking.
"It can't be!" Wendy giggled.
"It is though, look," the more he looked, the more Natsu was sure the patch of blue fur was Gray's guild mark. "It is Gray!"
All heads in the guild turned towards the small black kitten in Natsu's hands.
- Two days earlier -
"Is Juvia around?" Gray slid into the seat next to Natsu, "I need to take a job, and a little time alone would be nice."
"Nice to see you too!" Natsu commented with a grin.
"Sorry!" Gray looked flustered as Natsu gave him a quick kiss on the lips, a pink tinge spreading over his cheeks, "not here, people might-"
"It's okay," Natsu grinned at his boyfriend's blush, "no one's looking, and even if we haven't told them they all already know!"
Gray rolled his eyes, "Juvia obviously doesn't!"
"That, is wishful thinking…" Natsu shook his head, "have you found a job?"
"Yep, a wizard is apparently selling illegal spells to unknowing travellers."
"You want me to come along?" Natsu took Gray's hand under the table in his own, playing with his fingers, a small smile twitched at Natsu's lips when Gray didn't pull away.
"No, it's alright, should be a short job, I just need to find who it is and alert the police, I'll be back in two days."
"Suit yourself!" Natsu grinned, "you better get going before Juvia get's here, if you don't want to end up with a travel partner."
Gray nodded, he was about to stand but then turned and kissed Natsu deeply on the mouth before dashing out the guild hall.
Like Gray had said, it didn't take him long to find the wizard. A young man with short spiky blond hair and dark eyes, who thought he was so clever tricking the passing travellers into buying faulty, illegal spells. He could sense the strange magic coming from the shop instantly, he was going to just call over the police but his curiosity got the better of him, had he had to be sure this was the place…right?
Gray could feel the blond's eyes on him as he wandered through the small shop, yes, this is definitely the place. With a smile and a nod to the owner, Gray left, and in case the wizard was watching him, he walked the long way to the town police station. A couple of men followed him down to the shop, as soon as the wizard saw them he came out onto the street.
"I knew it!" He yelled, "You're one of those guild wizards aren't you!" He came out into the street and spat at Gray's feet. "I curse you! This one is going to be good, I can feel it." He shot a bolt of light at Gray which hit him in the chest.
Gray frowned, the light had done nothing, "ouch." He said sarcastically. "Now if you wouldn't mind, I have to go, thank you for the help guys." He then grinned, then waved before heading to the station.
"You will start to feel it soon!" The wizard yelled after him as he was bundled into the back of the police car.
Gray ignored him, and with a shrug, headed into the train stations building, that was when he started to feel strange. Holding his hand up in front of him he could see it starting to shake, wierd, that was when he felt like he was going to be sick. He staggered towards the mens room, then just as he got there everything around him began to grow, quicker and quicker until it stopped. Looking around he saw he was surrounded by a pile of material, wait…is that my shirt, my jeans? I know I strip but this is getting out of hand. He tried to take a step forward but fell flat on his face, wait, those aren't my hands, those aren't hands at all! "Oh no!" He tried to speak but all that left his lips was a loud and frustrated 'meow'. It can't be! He dashed out of the mens room and into the station, people looked like giants around him as tried to find his reflection. He had to be sure. Gray finally found a shop window where he saw, staring back at him, a small black kitten with large blue eyes.
"The train to Magnolia on platform two will be leaving in 1 minute. All passengers please board. The train to Magnolia will leave in one minute."
Panic settled in, I need to get on that train, Gray dashed towards the train, stumbling over and falling flat on his face a number of times, damn running on four legs! This is not normal! Finally he jumped onto the train, letting out a sigh of relief. Or it would have been if every noise he made came out as a loud 'meow' or a hiss.
The next hour was the scariest for Gray, the twenty minutes on the train were fine, he could hide away out of sight there, but once he was off the train people walked past him like he was nothing. A couple of them nearly kicked him. Forty minutes later Gray managed to slip into the guild hall as someone left and instantly looked for Natsu. He saw the mass of pink hair from the doorway and padded over. Winding his way around Natsu's legs, meowing to get his attention. "Natsu! Natsu! Notice me Flame-Brain!" Then finally Natsu saw him, his relief was short lived though, when he remembered that Natsu wouldn't be able to recognise him.
- now -
At the mention of his name, Gray looked up at Natsu, he sat, paws together at the front, tail waving slightly. It let out an indignant meow as Natsu gave him a scratch on the top of his head, then swiped at Natsu's fingers but the Dragonslayer was too quick.
"Hey!" Natsu cried out, "you do remember you have claws don't you Snowflake!"
Gray seemed to hear, as he did stop swiping at Natsu's fingers, but completely ignored Natsu's protest as he padded up Natsu's muscled arm and jumped up onto Natsu's head, curling up in the mess of pink hair. Gray purred contentedly, revelling in the warmth from Natsu's natural body heat.
"What are we going to do! Gray is a kitten!" Juvia panicked, staring, wide eyed at the dark bundle of fur atop of Natsu's head. The latter didn't have the heart to move him.
"We'll think of something, don't worry," Erza spoke up, butt the frown on her face didn't soften.
"I'll go get Levy," Lucy smiled, "though I don't really mind," she giggled, "Gray is adorable as a kitten."
Natsu rolled his eyes, trying but failing to pry Gray from the top of his head, wincing as he seemed to be pulling on his hair more than the stubborn cat he was trying to remove.
"What was the job he took?" Erza asked looking over at Mira, however to her surprise it was Natsu who answered.
"He was just a couple of towns over, dealing with a wizard who was selling illegal spells, you think the wizard did this?" Natsu abandoned trying to move Gray who seemed to have fallen asleep.
"There isn't any other explanation!" Carla piped up, eyeing the kitten warily.
"It does take a very powerful spell to keep a person in a different form like this, but keep their mind the same." Mira said, "Take Over magic takes a lot of effort performing it on yourself, but on another person…that would take a lot of power."
"It seems we underestimated this wizard." Erza spoke up.
"Aye!"
"So how are we going to change him back then?" Natsu asked, looking worried.
"That will be rather difficult," Levy cut in as she sat down opposite Natsu, looking around for Gray.
Knowing who she was looking for, Natsu indicated the kitten on top of his head, "what do you mean?"
"This sort of magic is a test of time, the caster can't even remove it, so Gray is stuck like this until the lacrima used runs out. That can be any time from a couple of days to a week, or even a month.
"A month!" Natsu exclaimed.
At this Gray sat straight up, startled by Natsu's yell, releasing his hold on Natsu's hair in fright he slid sideways and scrambled towards the door.
"Gray!" Natsu stood, oh no, "Gray!" He followed the kitten out the door but as soon as Gray had made it outside he disappeared. Damn it Gray! I'm sorry I startled you! "Gray!" That moment he head a bin topple out the back of the bakery.
"…and stay out!" An angry voice yelled.
Then he heard the sound of a boot connecting with something which let out a loud screech of pain. Natsu ran around the corner just in time to see a small black shape hit the wall then flop down to the ground with a thump. He waited until the baker was back inside before rushing over and picking up Gray in his arms. The kitten hissed in pain, his claws gripping into Natsu's hand but the latter didn't care as he rushed back to the guild hall.
A lot of fussing later Natsu had managed to convince the kitten into having a small bandage tied around what Levy suspected to be bruised ribs and possibly a sprained paw. By the time Gray had gone back to sleep atop Natsu's head it was getting late, and slowly the guild members had began to leave. "Gray can come back to mine tonight, that alright Happy?" Natsu spoke up.
The Exceed shrugged, "aye!"
"Thanks buddy!" Natsu flashed a cheesy grin, "well I might head back then, sleepy Gray here will probably do better anywhere but the top of my head."
The other's laughed, "I'll see you tomorrow then!" Lucy grinned, "see ya Gray!" She stroked the top of the kittens head before giving Natsu a wave as he left the guild hall.
Natsu reached his house with little incident, he gained a few confused stairs when they saw the kitten, but other than that Gray slept the whole way there. Once inside Natsu chucked an aprehensive glance at the hammock where he slept. "Now you…" he managed to pry the sleepy Gray off the top of his head, he placed him on the counter in front of him. "I hate to ask this, but seeing as you have been asleep on top of my head for most of the day, do you …you know, go…like to the bathroom."
Gray gave a loud meow, jumped off the bench and padded to the door. He then turned and stared up at Natsu.
"Okay, so if I open the door for you, you'll do what you need to do then come back?"
Meow.
"Okay then," Natsu grinned, and pushed open the door, Gray instantly trotted outside, "I'm going to make a bed up for you okay!" Natsu called over his shoulder.
Later that night, Gray was curled up on a bed of blankets and cushions near Nasu's hamock, asleep again. That was, only after Natsu had played a strange game of fetch with him (which he didn't even think cat's did). It had taken a while, but eventually Gray had gotten tired again and curled up in the make shift bed. "You really are just a bundle of pure fluff aren't you Snowflake?" Natsu smiled affectionately, "cute too…but I would love my boyfriend back!"
When Natsu woke the next morning he found Gray had moved to sleep on top of Natsu's scarf, the Dragonslayer had left it bundled on the couch the night before. Natsu laughed, at this Gray sat up, a length of the scarf flopped over his head, squishing down his large pointed ears. "You cutie!"
At this Gray shook his head, and sliding free of the scarf, he jumped down from the couch to wind his way around Natsu's legs.
"Whadya' think? Breakfast then back to the guild hall?" The loud meow he heard confirmed this as the plan, so Natsu started searching through the kitchen for something edible for Gray.
This went on for just over a week, Gray sleeping at Natsu's, finding it fun to chase Happy round the house, getting under everyone's feet at the guild hall and finding it fun to use Natsu's couch as a scratching post. One night however, Gray thought it would be fun to sleep on Natsu's chest instead of his scarf on the couch (he hadn't used the bed Natsu had made since day one). Gray liked the way Natsu's chest moved as he slept, it lulled him to sleep, plus it was warm. Natsu didn't have the heart to push him off, so that night they slept like that. Both perfectly content.
It was sometime around 3:00 in the morning when Gray started to feel a little sick to the stomach, oh no, before he had time to react he felt himself growing, ohno ohno, "shit!" He heard his own voice for the first time in over a week.
At that moment Natsu woke as the light bubble of weight on his chest evened out to be covering his whole body, and was a lot heavier. His eyes snapped open to see Gray's wide eyes centimetres from his own. He sat up in shock to see a full sized, stark naked Gray practically straddling him, the sudden jolt of movement unsteadied the hammock and it tipped the pair sideways. They tit the ground with a thump and a yelp as Natsu's back hit the wooden floor, he sat up again slowly, rubbing his head, staring open mouthed at Gray who had fallen next to him and was hastily pulling on the nearest pair of pants. (Gray wouldn't have usually minded but Happy was still asleep in the hammock next to Natsu's, having been surprisingly undisturbed by the noise.)
"God I am so glad to see you as you again! I mean, you were adorable as a kitten…but you're freakin' gorgeous as a human!" Getting to his feet, Natsu grinned.
Returning the smile, Gray crossed the room in two strides and pulled Natsu into a deep kiss, "man I missed that." He muttered into Natsu's lips, before giving him another quick kiss. "Now I need to sleep or I swear I will be cranky when I get to the guild hall eventually." He pulled one of the blankets from the makeshift kitten bed, then jumped onto the couch, he gave Natsu a look which screamed 'what are you waiting for?' before folding Natsu's scarf into a pillow of sorts.
Natsu slipped under the blanket next to Gray, "I'm glad you're back Snowflake!"
"You have no idea, Flame-Brain," Gray smiled into Natsu's neck, "just how glad I am too…"