A/N: I was looking through Pokémon fan fictions that were Palletshipping and rated M as well and I think there needs to be more out there, so I decided to write one myself.
I apologize in advance if it takes a bit for me to update this story, I'll try my best to get the next one or two chapters out as fast as I can.

Takes place when they are older I'd say around 18, also I only really watched the first two seasons of Pokémon so it won't have any characters besides the originals. If the beginning seems rushed, it's because I'm not great at starting stories.

Warnings; MalexMale relationship. Sexual situations between two males.

Disclaimer; I don't own Pokémon or any of the characters, all I own is my imagination.

Ash Ketchum was travelling through the woods alone in the Kanto region, why might you ask? Well he had finally become a Pokémon master but even that had happened about 6 months ago, he had actually went to visit Misty in Cerulean, it had been awhile since he seen her and Pikachu seemed really excited too. He was eating with Misty and her sisters who wouldn't leave considering he was now a famous Pokémon master, when he got a call from Bill. It was something about an experiment he had been working on, and was wondering if Ash would drop by so he could test it on him, though he wasn't really a fan of having something randomly tested on him, Bill convinced him saying it wasn't anything harmful and being the kind of nice, helpful kind of guy that Ash was he found it pretty hard to refuse.

Once he arrived at the Lighthouse Bill was at, there was a bunch of papers to fill out, which Ash wasn't in the mood to read and try to understand so he called Professor Oak, sent him what the papers said through email, he read through it and just briefly explained the whole thing. It was pretty much an experiment that was an attempt to mix Pokémon DNA with his own, of course it was temporary so even if it went wrong it would eventually wear off and he would return back to normal. The Pokémon who's DNA they had taken was from a Meowth, he was guessing it was from Team Rockets, since Bill mentioned it was one that could talk. Eventually Ash filled out the forms, apparently he was going to get paid this too so it wasn't all that bad. After leaving Pikachu with some snacks Bill had provided, he went to lay down on one of those tables used in medical centers, while lying there he looked up at the ceiling and saw a Butterfree fly into his view moments later; a sleep powder fell over Ash, his eyes slipped close as he slowly drifted into a peaceful sleep.

The trainers eyes opened to bright lights that he could have swore almost blinded him, he sat up slowly and looked around the room he was in when he spotted Bill walking over to him with a note-book and pen in hand, looking ready to take any notes if he needed.

"…So how'd it go?" Ash rubbed his eyes as well as stretched slightly while he waited for an answer.

"Well there are a few changes I can see, but other than that I would only know by what you tell me." Bill said, though sounded distracted while he wrote in his notebook. Ash eyes widened as he looked around for any type of mirror before spotting one on the other side of the room and making his way over to it.

"…What the..." Ash started but didn't complete his sentence as he looked into the mirror. On top of his head were small black cat ears, that even matched his natural hair color, and now that he was thinking clearly he also felt a tail which he automatically pulled his pants down a bit to see what it looked like, It was curled, just like a tail of a Meowth though his was longer, maybe because he wasn't as small as a Meowth, and it was also black but had a brown color at the tip.

"This is insane…I didn't expect any of this at all." The black-haired trainer said in disbelief.

"I actually find this to be pretty interesting… Is your sight or hearing any different?" Bill asked as he kept writing.

"Not that I have noticed… But I have feeling in both the ears and the tail which is kind of odd." Ash said as his finger tapped one of his ears lightly.

"I see, that's also pretty interesting. But I'll be right back." He said and he quickly left the room for a few minutes only to return with Pikachu following behind him. His best friend went over to him with a slightly confused expression, its head tilted to the side.

"Smells kind of like a Pokémon but I can still tell its Ash…" Pikachu said while smelling his leg slightly before just smiling up at him.

"Of course it's me buddy, just some experiment thing." Ash said in a happy tone, before he stopped to think for a few seconds.

"Wait! I know I have a general understanding of what you mean but it's usually just the basics… Does this mean I can understand Pokémon?!" He yelled turning to Bill quickly.

The researcher eyes widened before he wrote it down and called pulled out another Pokéball to test it, sending out an Eevee which Ash fully understood it as well. After completing a few more tests to see if there were any other changes Ash got ready to head to Pallet town. Bill had contacted Professor Oak, and it was decided that Ash would stay in his hometown until the effects of the experiment went away, since he'd be more comfortable there and Professor Oak's observing skills were pretty good as well. Ash was told to try and make sure no one notices anything besides professor oak, his mom and people he could trust not to tell, so he travelled back to Pallet with hardly any stops along the way, his hat covered his ear though it wasn't all that comfortable and his tail was easily hidden in his pants. When he went to sleep it was camping out instead of sleeping in the towns like he would usually do when he could.

Upon arriving in his hometown Ash was greeted by his mother, who seemed a bit panicked probably since she thought the experiment had some negative side effects. After calming her down a tiny bit, by showing her his ears and tail plus explaining he made his way over to Professor Oak's lab with her so that she could get some type of confirmation for professor Oak, he knew that hearing it from someone with more knowledge on the subject would make his mom feel better.

As he entered professor Oak lab after his mother who was well ahead of him in need of some calming down he made his way over to the two older adults and again took out his tail and removed his hat since he was sure that Professor Oak would have asked him moments later to see anyways.

"Very Interesting, I just finished rereading Bills observations of what changes he noticed just before you two got here. Is it really true that you can understand what the Pokémon are saying? If so this could be a great discovery…" Ash nodded in response, then explained the situation on when he woke up and Pikachu was brought in. After explanations and a ton of questions were asked, Ash and Delilah left for the night, leaving to have dinner together that they haven't had in quite a while. As Ash was at the front door about to open the door to leave the Lab, the door was abruptly slammed open hitting him in the face and making him fall backwards to be seated on the ground.

"Sorry about th- Oh it's only you Ashy boy, no need for the apology then." Gary said with a smirk in Ash's direction before he had even looked Ash over to see that he was alright.

"Do you always slam the doors open like a crazy person?" Ash said as he rubbed his face, not noticing that his hat had fallen off and that the shock from being knocked down had then up twitch slightly only going slightly back because of the pain he felt.

"You're just jealous because I know how to make an entran- That's one weird fetish you got there." The rival said slight surprise followed by a laugh, as he reached down to flick at one of the cat ears slightly to highlight what he was talking about.

Ash winced slightly the ears flattening against his head. "Don't do that! They happen to be pretty sensitive…" The Pokémon trainer said as he gently went to rub the ear that Gary had just abused.

Gary blinked in surprise as he moved closer to inspect the ears. "W-What those things are real?!" Shock was fully evident in the voice of the Ash's rival.

Ash's mom coughed slightly before talking "I'll leave you two to catch up and explain things… I still have a dinner to make, Ash make sure you are home in an hour alright sweetie?"

Ash nodded as his mom left the lab, closing the door behind her before he turned back to his rival clearing his throat slightly before he talked. "Yeah… They are real, Bill convinced me to take place in experiment of his and they are one of the effects it had."

"Really? What kind of experiment was it? … They look really soft." Gary trailed off in a tone that had some form of amazement in it as he gently reached to pet the ear that he had flicked, pushing Ash's hand away from it in doing so before he began rubbing it slightly in the one of the only form of apology Gary would use around the other trainer.

"Mixing my DNA with a Pokémon's…" Ash's voice got quieter near the end of his sentence, the feeling he was getting from Gary rubbing his ear making him feel odd, he could feel the blood rush to his face as he looked away at the same time pushing Gary's fingers away from his ear. "I-It's fine now, just don't go flicking them again."

"Alright Ashy boy, though I wasn't really worried about them, just wondering if they were soft or not. Anyways I was thinking of having a Pokémon battle but since you are part Pokémon in some way now I doubt your Pokémon would see you as their trainer, considering it was probably hard enough for them before." Gary said with a shrug, a small grin across his lips, the one Gary always used to show how superior he was to Ash.

"Bring it on! My Pokémon will still know I'm their trainer and beat you either way!" Ash shouted, even at the age of 18 their rivalry was still as childish as it was when they were younger, and Ash doubted that would change anytime soon, there was just something about his rival that got him going whether he wanted to or not.

"Don't say I didn't warn you if they don't listen to you, to make it easier on you we'll just have and one on one battle this time." Gary said with a smirk as they made their way outside for their Pokémon battle. As usual once they got outside they choose their original starter Pokémon, Pikachu and Umbreon, there was just something about battling with the first Pokémon they got that came automatically to them, maybe it was in their minds the best way to prove who's Pokémon was stronger but neither of them ever mentioned this fact. Shortly after Umbreon was sent out, it looked at Gary and talked, though of course Gary didn't hear it talk just heard it repeat its name a few times, not that he didn't understand what his Pokémon was saying, even though Gary didn't always have his Umbreon out like Ash had his Pikachu out, the trainer and Pokémon still had a close bond and great understanding of each other.

Ash blinked a few times in shock as he heard Gary's Umbreon talk, saying "Ash huh, another one of our favorite battles, you should really just hang out with him more when you really just want to be closer with him."

"…What does your Umbreon mean by you wanting to be closer to me?" Ash said sounding pretty confused, last time he checked Gary could barely stand him, which is why battling was the one of the only ways they really communicated now.

"..What?" Gary blinked a few times before looking at his Umbreon, who blinked up at him before looking back to Ash. "You can understand my Umbreon?" Ash rubbed the back of his head nervously before looking to the side slightly.

"Yeah... It's another one of the side effects I have." Gary stared at Ash for moment unsure of what to say, when Pikachu decided to speak up instead, though Gary had no clue what Ash's Pikachu was saying, since it wasn't his Pokémon.

"Umbreon always says things like that before the battle, but I figured it was rude to eavesdrop and tell so…" Pikachu said while looking down slightly, worried that Ash was mad at him in some way for not informing him of this before. Ash blinked in shock a few times before reaching his hand down to pet his best friend on the head in reassurance.

"No you were right to do that, I just wasn't able to ignore it." Pikachu perked up before smiling happily at his trainer. Gary started in amazement before his mind went back to what Umbreon had said, should he just ignore it and say they should get on with their Pokémon battle, he felt himself panic internally for a moment before deciding on the latter.

"Anyways Ash, now that you're done conversing with your Pikachu, let's get this battle on the road." Gary said confidently, forcing a grin on his face even though he wasn't feeling all that confident in that moment. Ash nodded and decided if he was going to ask Gary about what his Umbreon, now didn't seem to be the time to do that.

"Bring it on!" Ash said getting over energetic like he usually did when he knew he was in for a great Pokémon battle. As they battled it was really close and hard to tell who was going to win, Pikachu's agility helped a lot in making it so not much of Umbreon's attacks hit, but Umbreon was just as fast, it seemed the battle wasn't going to end anytime soon, both Pokémon had only been able to land one attack on each other. They were both nearing the end as both Pokémon ran out of energy both using an attack at the same moment, Pikachu using Thunderbolt and Umbreon using Psychic, Umbreon dodged perfectly, even as an Eevee it was great at dodging attacks like they were nothing at all, though it did tire the Pokémon to some extent. Pikachu wasn't as lucky, though it had almost managed to avoid its attack, the attack ended up hitting his tail, which happened to be a bit of a weak spot for the mouse Pokémon, causing Pikachu to faint from the exhaustion combined with the attack on its tail.

"Pikachu are you okay?!" Ash yelled before quickly running to his Pikachu's side picking and kneeling down to pick it up gently. Pikachu slowly opened it eyes with a small smile.

"I'm okay... That was a pretty good battle, huh?" Ash nodded at his Pikachu with a smile.

"Sure was buddy… Anyways I think we should go home where you can get some rest and food, mom's probably done cooking right around now." Ash said as he stood up from his kneeling position and turned to walk towards his house, almost completely forgetting his rival was still around, focusing on his hunger at that moment.

"See ya Ashy boy, I guess I'll bug you tomorrow." Gary said with a smirk, before turning around himself and heading back towards his grandfather's lab.

"It was fun battling you Gary, I'll be sure to beat you next time we battle!" Ash yelled before running off to his house still carrying Pikachu in his arms. Bringing an actual smile to his rivals face.