Pokemon One-Shots and Headcanons

Path to Choose

It had been four years since Greninja and Ash had parted ways so Greninja could help Zygarde protect Kalos. With most of their work in that region now complete, Greninja had departed from his legendary friend to travel the world and see some of the other regions. He was currently in Kanto, watching a pair of young trainers, one girl and one boy, battle.
"Bulbasaur, use Vine Whip!" the girl shouted.
"Bulbasaur!" the small grass-type screamed, lashing out with her vines and hitting the boy's Charmander over the head.
"Charmander, Flamethrower!" the boy called out. Charmander emitted a burst of flames that sent Bulbasaur flying backwards, knocking her out.
"Bulbasaur, no!" the girl cried, running over to check on her Pokemon. Greninja saw her visibly sag with relief when she saw that her partner was all right. "Okay, let's get you to the Pokemon Center," she said.
The boy walked up to her. "Good job, Lucy," he said. "You've gotten a lot better since I last saw you."
"Thanks, Kevin," Lucy replied. "Want to come with me to the Pokemon Center? Your Charmander probably needs healing too."
"Sure, all right," Kevin agreed. "Let's go, maybe we can see Ash."
Greninja froze. Ash? he thought to himself. He's here?
Then another thought hit him. Oh, right. I'm an idiot. Ash's home is in Pallet Town, Greninja thought, smacking his forehead mentally. Well, if he's here...
Before Greninja could even begin to make his way towards the Pokemon Center, however, he was stopped by the sudden appearance of a teenage boy who looked to be about Ash's age-that is, Ash's age now, not the last time Greninja had seen him. The boy had brown hair and was being followed by a crowd of cheerleaders.
"Well, what do we have here?" the boy asked, staring at Greninja. The frog-ninja Pokemon scowled, not liking the boy's tone. "Some sort of rare Pokemon? Let me see..."
He pulled out a Pokedex and aimed it at Greninja's face. Greninja sighed and crossed his arms, waiting for the strange boy to finish scanning him so he could go see if Ash was around.
"Greninja, the ninja Pokemon, and the final evolved form of Froakie. Greninja can craft water into sharp-edged throwing stars. With the grace of a ninja, it slips in and out of sight to attack from the shadows."
"Wow, pretty cool," the boy said, stuffing the Pokedex back in his pocket. "Though I have no idea what a Froakie is..."
Greninja rolled his eyes.
"But whatever," the boy said, pulling out a Pokeball. "I think I'm going to catch you. Go Pokeball!"
Wait, what? Hey, I don't want to be caught by-
It was too late. The Pokeball hit the bipedal frog Pokemon on the left shoulder. Greninja shut his eyes and waited to be sucked inside.
But instead, the Pokeball simply dropped to the ground. It hadn't been able to do a thing.
"Wait, what? But how?" the brown-haired boy yelled angrily.
"Wait, but how come it didn't work?" Greninja wondered aloud, though all that came out to the boy was a "Greninja, gren?"
The boy, fuming now, turned away and stormed off. "Whatever," he muttered. "I'll just get another one."
Greninja sighed with relief and continued on his way to the Pokemon Center. He hoped Ash would still be there when he arrived-if he was there at all. A little while later, however, he ran into the same boy who had tried to capture him earlier. This time though, he was talking to a very familiar raven-haired boy with an equally familiar Pikachu on his shoulder.
"Well, well. If it isn't Ashy-boy," the brown-haired boy said in a mocking tone. Greninja felt a spark of irritation flare up inside him.
"Oh, hey Gary," Ash replied. "I see you've still got that crowd of girls following you."
Gary smirked. "You're just jealous that you don't have as many fans as me, Ashy-boy," he said smugly.
"I'd rather not if I'd look like a moron like you," Ash replied irritably. Greninja smirked a little at that. It seemed that Ash had changed a bit over the years, although that was to be expected.
"Idiot," Pikachu said, glaring at Gary. Now, Pikachu on the other hand....
"So what have you been up to, Gary?" Ash asked conversationally.
"Nothing much, challenged a couple regions, on my way to Kalos now," Gary replied. "I'll be sure to win the league there."
"Gary, Gary, he's the man! If he-" the girls started to chant the most annoying cheer ever in Greninja's opinion until Ash, thankfully, stopped them.
"Shut up!" he snapped. "I am not listening to any of your Arceus damn cheering today!"
"Tell us how you really feel," Gary muttered. Ash fixed him with a glare.
"You can shut up too," he added.
"Oh, I also tried to catch a Pokemon just now, but it didn't work out so well," Gary admitted.
Ash's annoyance faded and was replaced by interest. "Really?" he asked. "What kind of Pokemon was it?"
"I think it was a Greninja," Gary answered. Ash's eyes widened in shock.
"Wait...a Greninja?" he stammered. "You're sure?"
"Yeah, scanned him with my Pokedex and all," Gary said, looking puzzled. "What about it?"
"I think I know why your Pokeball didn't work," Ash muttered. A bit louder, he asked, "So where is Greninja now?"
"Right here, Ash," Greninja said, jumping to stand next to his old trainer. Ash jumped, startled by Greninja's sudden appearance.
"Greninja!" he exclaimed. "How-what-"
"Hi, Greninja!" Pikachu said, waving at him happily. Gary stared between the three in shock.
"You know this Greninja?!" he asked in stunned anger.
"Uh, yeah. Greninja was one of my partners in Kalos," Ash replied, rubbing the back of his head. Greninja smiled at the familiar action. It was nice to see that some things hadn't changed. "I had to release him so he could take care of the region-long story there-but I never did anything to his Pokeball, which is probably why it didn't work when you tried to catch him."
Greninja stared at Ash in shock. His Pokeball was still intact. Which meant that, technically, he was still Ash's Pokemon.
Oh well. It wasn't like he was going to complain. Ash was a pretty great person to be stuck with, after all.
Gary looked ready to pop a vein.
"You selfish bastard!" he snapped. Greninja scowled at him.
"Me? How am I selfish?" Ash asked, seeming genuinely confused.
"You're preventing me from catching that Greninja!" Gary shouted.
"Well, I'm sorry that I didn't destroy Greninja's Pokeball, but I don't see why you're so upset," Ash replied calmly. "You could always go to Kalos and pick up a Froakie and, you know, raise it to become a Greninja."
"No can do," Gary snapped. "I want that one, and you're going to give him to me."
"I'm afraid I can't, actually, since I technically did release him," Ash told him. "So I can't really tell him where to go and where not to go."
I think I know where I want to go though, Ash, Greninja thought to himself.
Gary seemed extremely pissed off now. "Fine then, we'll have a battle!" he snarled. "Winner gets to take Greninja!"
Greninja stared furiously at Gary. Hell would freeze over before he agreed to be used in a bet like this. Ash glared at him. "Sorry, not interested," he said angrily. "See, I'm not exactly in the business of using my friends as betting chips."
If either of the boys had glanced towards the frog-ninja Pokemon now, they would have seen his eyes light up. However, Ash was too busy glaring at Gary and Gary was too busy fuming.
"I'll tell you what, though," Ash said calmly. Then, to Greninja and Gary's surprise, he pulled out what Greninja knew to be his Pokeball and handed it to the froglike Pokemon.
"Ash? Why are you giving me this?" he asked.
"You decide if you want to go with him or not," Ash said to Greninja, completely ignoring Gary's presence now. Indeed, it seemed as though he were ignoring everyone around them. "I know you can decide what you want to do with your life. So I'm giving you your Pokeball because I can't keep it anymore. Because keeping it would just be another way of forcing you to stay, and it's not fair of me to do that."
Greninja smiled and shook his head, pushing the Pokeball back towards Ash. Ash took it, looking surprised.
"No?" he inquired.
"Ash, I appreciate your thoughtfulness, but I don't want another trainer," the frog-ninja Pokemon said. "I'm more than happy to stay as your Pokemon."
Ash smiled. "Well, if you've made up your mind..." He held out the Pokeball and Greninja bumped it with his fist without hesitation.

Yeah, I made Gary an asshole in this one. I like writing stories with him as a jerk since he was one of the most annoying characters in the anime in my opinion. And, come on. Anyone who has a group of cheerleaders following him around has some serious ego issues.