Honestly, after Ash and his mother had waved goodbye to Principal Oak and the other students, Kukui hadn't expected to see the boy again. But he did have plans – the moment he had approval to begin building Alola's Pokemon League, he was absolutely going to invite him back to take part. There weren't enough battle trainers that lived on Alola to justify it, but he figured that if he sold it like that Battle Frontier thing… maybe… maybe competitors had to be alumni of multiple leagues… maybe they had to have achieved a certain rank in each of them…

He was still considering it the next morning, when he wandered onto school grounds only to find Ash standing in the courtyard and staring up at the main building.

"Where was the Principal's office again…?" he was muttering quietly. The pikachu he'd had out all day yesterday was perched on top of his hat and looking equally lost, staring in the opposite direction of wherever Ash turned his head.

"Pika… pika?"

Kukui smiled and started walking again. "Forget something, Ash?"

His shoulders jerked, and then he turned, eyebrows rising curiously. "Professor Kukui. Alola!"

"Alola," he replied with a chuckle. Ash seemed to have latched on to the word much better than most tourists – he didn't have the slightly patronising edge you usually heard when foreigners tried to mimic local language. You could almost think he'd been using it his whole life. "I didn't expect to see you back here again."

"About that…" he said, lifting a hand to the back of his head. "I actually wanted to ask about enrolling."

"En-" He blinked, then frowned. "I thought you were just here on vacation."

"I am. But Alola is so amazing – a weekend hasn't been nearly long enough!" he said, spreading his arms while Pikachu enthusiastically gestured and cheered along. "There's so much I still want to see! The Z-moves, and I want to see a Trial! And the Guardian Pokemon, like Tapu Koko and the others! I want to meet them all!"

Kukui chuckled, shaking his head. "I can't say I blame you, but you should know that even most Alolans go their whole lives without seeing any of the Guardian Spirits. I haven't ever met one."

"That's okay! There's still heaps to learn, even if I never see them again!" he said happily, then pulled back a little, reigning in his enthusiasm to explain. "Y'see, I want to be a Pokemon Master, and that means I need to learn everything I can about pokemon from all over the world! And that's why I want to enrol in this school! Just for a year or so."

He had to smile. As a researcher, he always approved of people wanting to learn more about pokemon, and as someone who studied moves, he especially approved of battle trainers looking to expand their horizons. But still. "And what does your mother think of all this?"

"I haven't told her yet," he admitted, while Pikachu pulled back in an amazing mimic of Ash's suddenly contrite expression. "I wanted to check with Principal Oak to see whether I could enrol here first. It's not like the other regions I've been to, where there's a league to compete in. Here, if I can't study here, I'd really just be taking an even longer vacation. It's better to have a goal, you know?"

Again, Kukui found himself approving of the argument, even if he had to squash the urge to roll his eyes in exasperation. It had been so long since he'd been to the Eastern regions – he'd forgotten how soon kids considered themselves independent there. Of course Ash, who here on Alola would've still been adhering to curfews and asking permission to visit a friend's house after school, considered his mother a secondary concern to arranging his own plans.

Not to mention – "And where were you planning to stay while you were studying? Pokemon Centres don't take long term guests, and somehow I doubt you brought enough gear to camp out for a year."

"We'll work something out," Ash said cheerfully, and Pikachu pumped its fists in agreement.

"Pika pika!"

Kukui just stared at him for a few moments. Somehow, he actually believed him. He had a sudden mental image of the kid slouching back against a tree for the night, as comfortable as anyone else in a bed.

On the other hand, Kukui had a loft with a futon going to waste.

He remembered the Quick Attack he'd seen yesterday, and that Thunderbolt that had almost effortlessly fried three salandit. He remembered Ash's confident smile, and how he hadn't even hesitated before jumping in to help a complete stranger, just because the fight wasn't fair.

He wondered if Ash really had seen Tapu Koko.

He wanted to get to know the kid.

Kukui took one more step forward, smiling as he reached a decision.

Honestly, Kukui hadn't really known what to expect when he agreed to take Ash into his home. It wasn't the first time he'd boarded a student, but normally, the kids he took in weren't so… enthusiastic.

"This is so cool!" he cried, spinning around with his arms spread wide. "I can't believe you have a training room in your lab!"

"Well, I was a pretty serious trainer before I became a professor. Even took on the Kanto League when I was just a little older than you," he said, and was gratified to see Ash's eyes go wide with awe.

"You competed in the Kanto League? How many badges did you get?"

"All eight; all won through battle," he said proudly. "I actually won the whole thing. Got through three of the Elite Four, too. But that Lance sure put me in my place."

"Yeah, he's super strong," Ash agreed, before pumping both fists. "But I can't believe this! You're a League winner? And to get to Lance you must've even beat Agatha! That's so cool!"

He grinned. He didn't often get to brag these days – everyone on the islands knew he'd won, and it had been so long ago that no one was particularly impressed by it anymore. It was nice to have someone overlook the time difference to see the accomplishment. "Well, that's all in the past now. These days I mostly just study moves for my research."

"For your research? You mean you're not just a teacher, you really study like Professor Oak and the others too? Whoa, Professor Kukui, is there anything you can't do?"

He laughed. "You don't have to flatter me, I already agreed to let you stay here," he said, even as he revelled in the praise. He was definitely telling Burnet about this. "But yeah. I study moves and move-sets. Right now, I'm looking into why pokemon can only seem to know four moves at any one time."

"Oh yeah, I guess that is kind of strange," he said, and then folded his hands behind his back, rocking back and forth on his heels. "But some pokemon have abilities that seem a lot like moves, and they don't seem to count. And if you train them right, they can kind of do moves that seem like new ones, but they don't count either."

He tilted his head, intrigued. "What do you mean?"

"Well, you know…" He rolled his eyes as he tried to find a good example. "A water-type can cloak their whole body in water, right? And the water takes whatever attacks get thrown at them. Kind of like a Protect, only it doesn't count, because all they're really doing is using their surroundings."

Kukui blinked, his hand blindly reaching for a notepad behind him. "You've seen this?"

"Sure, loads of times!" he said brightly. "It's actually how I started teaching my pokemon to use Counter-Shield."

"Counter-Shield?" he repeated. He'd heard of Counter, and Shield, but Counter-Shield?

"Yeah. It's a move I made up. You wrap yourself up in attack power, so anything that tries to hit you just gets hurt instead," he explained, flicking his wrist to wave it off like it wasn't important. Kukui scribbled the name down as a reminder to himself to ask about it later as Ash continued. "But that is a move. I'm talking about a cloak. You see it a lot with water-types, but I think flying-types do it way more often, using air currents and stuff. But since you can't see air, it just looks like they're dodging."

"That…" Kukui blinked again. "That's very true…"

"And sometimes, it's not even like that. It's like when a fire-type uses flames, but it's not ember or flamethrower, it's just fire that they can make. And like how ghost-types can totally ignore physical attacks, and for dark-types, it's like psychic abilities just don't exist at all!"

He… had never really thought of it like that. "But for ghost- and dark-types, those things are just part of what makes them their type."

"Just like water makes a water-type," Ash pointed out. "And how a fighting-type is all about hitting stuff as hard as you can. A pokemon is more than their type, but they're all connected to it, right? Even if all you train a butterfree in is psychic or physical attacks, that doesn't mean it can never make stun spores again. Right?"

"It just… doesn't use them in battle," he said slowly, and quickly wrote down the comparison. It was things like that that had first intrigued him about studying moves, but he hadn't ever applied it on such a wide scale. But Ash was absolutely right – you could teach an incineroar nothing but fighting and dark-type moves, making it forget all the fire it had ever known, but that fire was still there. So, in theory, it could still be used. Maybe not as a move, per se, but…

"Oh, wow, is this a moon ball? Hey, you've got all sorts of pokeballs in here! Are they registered to anyone? Are there pokemon in here?"

He glanced up from his notepad, disoriented. "What?"

Ash was pawing through one of his boxes, somehow on the other side of the room to where he'd been without Kukui even having noticed him moving.

"Uh, no, they're just spares. I give them out sometimes to my graduating students. What was that you said about –"

"Hey, a lure ball! I used one of these for my totodile," he said, holding it up with a grin. "It's the only special one I've got. I always just buy the ordinary ones."

"You have a totodile?" he asked blankly. He hadn't seen Ash carrying any pokeballs – not even one for Pikachu. He shook his head, trying not to get distracted. "Is that who used the water cloak?"

"Nah! Totodile's really good at dodging," he said, and then seemed to make eye-contact with the lovediscs in the tank, and hurried over to press his hands against it. "Hey Lovedisc! Wow, that's so cool! Look at those scales! You're so beautiful!"

Kukui sighed, rubbing the heel of his hand against his temple. He was getting the distinct impression life with Ash was going to be a little exhausting.

"You've been in how many leagues?"

Ash made a face and rocked back to think. Eventually, he released his ankles and started counting on his fingers. "You could count the Orange Islands, and the Battle Frontier, but um… well, Kanto, Johto, Hoenn, Sinnoh, Unova, Kalos… I guess six. I didn't do very well, though," he added with an embarrassed laugh, before he shrugged with a broad grin. "I made it to the finals last time, though! Alain was the better battler, but we did pretty good!"

Kukui stared at him, then touched his hand to his chin, wondering if he could somehow take advantage of Ash's experience. Then he realised how creepy that sounded, even in his own head, and laughed a little to move on. "So that means you must have a full team at home. Pikachu, and you mentioned Totodile last night. Who are the other four?"

"Other four?" he repeated.

"The rest of your team," he prompted, but Ash only continued looking at him blankly. He scratched the side of his head, not really understanding how Ash was having trouble with this. "You need six registered pokemon to compete in a conference."

"Yeah…?"

"So if Pikachu is one, and Totodile is another…?"

"Oh. Well, it depends on the battle," he said, still blinking wide eyes like Kukui was the one not making sense. "I switched my team around a lot for the conference Totodile helped out in."

When he didn't expand on that, Kukui chuckled a little helplessly. He was quickly learning Ash wasn't really one to pick up on subtle cues or volunteer information you didn't directly ask for. "So you must have quite a few pokemon then."

"Uh huh! Most of them stay at Professor Oak's lab. They like it there, because they get to hang out with a whole lot of different pokemon," he explained. "But Pikachu always comes with me to new regions. He's my partner!"

Obviously having heard its name, Pikachu looked up from where it was playing with Rockruff just long enough to smile and chirrup some kind of acknowledgement. Ash grinned at it before coming back to Kukui.

"How about you, professor? Do you have any other pokemon?"

"Of course," he said with a nod. "But they're a little big to keep around the house."

"Big pokemon, huh? That's so cool, I can't wait to meet them!" he said, bouncing a little. "It's the best thing about coming to a new place – getting to meet all kinds of pokemon you've never seen before."

He tilted his head, amused by the enthusiasm. "Do you have a specific type you favour?"

"Favour? You mean do I have a favourite type of pokemon?" he asked. "No way! All pokemon are amazing!"

"Of course," he said with a laugh. He should have expected that.

"Professor Oak," Kukui said, with all the respect and honour due a man globally known as The Pokemon Professor, inventor of a device used by every pokemon trainer under the age of thirty and leading expert on Pokemon-Human relations. And his very eccentric boss's cousin. "Thank you for taking my call."

"Of course," he said, peeling what looked suspiciously like stringshot webbing off the side of his face. "Thank you for agreeing to board Ash. He's a close friend of the family, you know – my grandson's best friend and one of my more…"

Kukui blinked as he waited for Oak to finish his sentence. Apparently he was struggling to find a suitable word. After almost a minute had passed, Kukui decided to lend him a hand. "Experienced? Devoted?" His grin widened. "Enthusiastic?"

"…honestly, I'd call him a fascinating case study, but I don't think it does him justice," he admitted, then smiled brightly. "I hope he isn't causing you too much trouble."

"Oh, not at all," he said. It had only been two days, but aside from his apparent rivalry with a living god, he doubted Ash would be a problem. He ate a lot of food, faster than seemed humanly possible, but he was otherwise surprisingly self-sufficient. Still adapting to having to be specific places at specific times, but so far he had been nothing like any of Kukui's other boarders. He hadn't needed to remind Ash to do anything or find ways to entertain him, and Ash had been the one to raise the question of how chores should be done – on the very first night, no less. Apparently he'd learned the value of sorting that sort of thing out early. He was a very proficient dish-washer. Kukui smiled at Oak. "I wasn't aware of just how much experience he has a trainer, however. He tells me he has quite a few pokemon over there – I was hoping you could provide me with his pokedex records. I would hate to try and teach him something he already knows."

"You would never know if you did," Oak advised. "In fact, while I don't mind compiling it, I doubt the list would be beneficial. Ash has seen many pokemon—far more than you or I, I suspect—but he would be the first to tell you he doesn't know everything about them."

His smile widened a little. Samson had told him Oak spoke of Ash with something suspiciously close to paternal pride, but a renowned professor letting affection blind him to basic realities—any young trainer having seen more pokemon than The Pokemon Professor, hah—was rather sweet. "Still. If you wouldn't mind sending it through."

Oak shrugged and made a note for himself. "I'll send you the list of his team, as well. Which reminds me, as fair warning. Don't be altogether surprised if, should he put together another team there in Alola, it seems more like the pokemon choose him. It's something of a habit."

"Oh? I would have thought a battle trainer like Ash would select his pokemon with a strategy. I've no doubt he would bond with them quickly, but most battle trainers rely rather heavily on –"

Soft laughter cut him off. "If I were you, I would abandon that thought while you can. While Ash has relied on the pokeball connection before—bug- and flying-types, usually—it's not his standard, by any means," he said. "The battle, if it happens, is usually more of a formality."

"Interesting," he said. "And, I suppose, appropriate for one of your premier trainers. A true example of the best in pokemon-human relations."

"Hah!" Oak didn't look nearly as amused as Kukui had expected. "As I said, a fascinating case study. And one that should be experienced first-hand."

He blinked, not really sure how to take that.

"Forgive the abruptness, but I really should get back to my research. Is there anything else I can do for you, Professor Kukui?"

"Oh, no, thank you very much," he said. "Good luck."

"Thank you. You can expect those lists by the end of the day. Good luck to you as well," he said, and then smirked. "You'll need it."

Kukui raised an eyebrow, but wasn't given time for anything else before the call went black.

Then he got the lists.

Kukui stared at the first one for a long time, noting the geographic date stamps registered to each one, claiming they had been visual matches, rather than Ash just looking them up for research. Kukui didn't recognise a third of the pokemon listed – he'd never been to Unova and his time in Kalos had been very brief, while his visits to Sinnoh had mostly revolved around Burnet, not pokemon.

He sent a quick note back, checking to make sure this wasn't a compiled list from trainers that had set out on their journey at the same time. Oak's assistant sent back a confirmation, with apologies that it wasn't complete – Ash had apparently gotten progressively lazier about scanning pokemon in Kalos, and had apparently always been prone to skipping it 'in more unusual circumstances'. Kukui wasn't quite sure what to make of that.

The other list was much shorter. For a battle trainer, Ash apparently didn't catch many pokemon. He'd come close to a more standard catch-rate in Unova, but then dropped significantly in Kalos. Checking the fifth registration for Kalos a second time, Kukui sent another email, and the assistant quickly replied that yes, it was correct, but no, they couldn't send any further data. Goodra apparently hadn't made it back to Kanto.

It was a habit, the assistant apologised. But if Kukui was interested, the Kalos league had been filmed and PokeVision would probably have videos of a few of Goodra's battles.

He went upstairs and spent a few seconds just staring at the boy on his couch, who was enamoured of his new rowlet's soft feathers and gushing about how strong its kicks were.

Then he quietly went back down to his office, and considered what kind of qualities a Guardian Deity would respect in a human.