The explanation

Sora's mind was reeling in with the events of the past few minutes. A super powerful Digimon that Izzy created himself defeated all of their Digimon. Then Demonicamon proceeded to torment them all by causing the ones closest to them great pain. Sora replayed her feelings at that moment in her mind, and trembled all over again.
Demonicamon could have killed them all after defeating the Digimon, but she only wanted to torture them. Sora looked at the new kid as stood up shakily. He said his name was Ash, and he was from some town called Pallet. The kid Ash appeared after Izzy's fail to send his creation through the Digital Gate he formed. Unfortunately, she was too powerful and broke free, and then Ash seemed to be pulled through the gate. Sora looked at him, he seemed to be about her age.
He wore a blue jacket, and had a black t-shirt inside of it, blue jeans, and he also wore a red and white hat with a weird green symbol. But he also had a rather cute yellow Digimon he cradled in his arms. She wondered if he was a new Digidestined Child? Although Ash didn't call it a Digimon, but a Pokemon. The way he held and care for it looked like they have been together for a long time. Even after around of introductions, he still seemed shaken and disoriented.
Ash looked about himself, "Is there a phone nearby so I can call home?" He asked Sora. Sora noted that he seemed to genuinely have a clues to where he was or what he was doing here. Although still visibly shaken by his experience, he displayed a sturdy, but weak smile. Sora couldn't remember if she fared so well after her first trip to the Digiworld, but the boy, "Ash" seems to have a strong resolution. "Er...Sora I think you said? Well is there? A phone I mean." Sora was lost for words. How could she begin to explain to Ash about the Digiworld?
"Ash, I'm Izzy." Izzy strolled forward and offered his hand in friendship. "There's a lot you don't understand about what's going on, but we need to get out of this area and to a safer location. Then we can properly share stories."
"You mean this place, wherever I am isn't safe?" Ash asked and looked about him. He seemed to survey the many scorched patches of earth and blast craters. "Hmm, it does look as if a battle of some kind went on here, there must have been some powerful Pokemon involved." Ash said thoughtfully. He looked down at the yellow creature, he held in his arms. Sora noticed it recovering slowly. "And my Pikachu, is still weak from what happened at Professor's Ivy's Lab, So I'll follow your advice for now, but the minute we get to a save spot, I want the whole story as to where I am." What was a Pokemon and who was this Professor Oak they would have much to discuss later.
Tai had been kneeling by his sister's side, but had been listening to Sora hoped the painful shock the rouge digital woman gave Kari, T.K, and Mimi had no lasting effects. Tai stood up and looked into the red sky and said, "We don't how long it will take for us, so we need to go somewhere far from here and as safe as possible." Tai had a way of taking control of the situation, but Sora had grown to trust his decisions. Tai then cast a disapproving eye on Izzy, and said "Then Izzy we need you to come up with some why we can fight that thing."
Izzy face clouded over with a mix of sadness and shame that Sora could feel just from looking at him, but true to his problem solving form, Izzy said, "We need to get to Gennai's place. It's about a days walk from here and there are some caves on the way we can hide out in." Izzy looked down and rubbed Tentomon on his head and continued, "When we get to those caves we can trade stories with Ash and bring him up to date on where he is and where he came from."
Sora hoped Ash would not mind having all the details of where he is and how he got to the Digital World. She looked over and saw that he had moved to where Kari was setting down. The child seemed to be okay young face showed how frightened she was. Ash knelled down next to her to and looked over Gatomon, who was sitting in her lap. "That is the strangest Meowth I've ever seen. I know that Pokemon tend to vary from region to region, but I've never seen this variation of Meowth." Ash seemed more interested in engaging the little girl in conversion, perhaps trying to cheer her over. "I'll say one thing, this is one cute Pokemon."
"Hey watch what you call me! I'm a Digimon and the name's Gatomon!" The digital cat said while being a little peeved, she jumped out of Ash's hand and stood next to Kari. "And watch the fur! I just groomed myself."
"Ah! It can talk!"Ash said quite surprised, he almost fell backwards. Which seemed to startle the yellow mouse awake.
"Of course I can talk, all Digimon can!" Gatomon said with a small sneer.
Sora decided to speak up. "Like we said Ash, it seems we have a lot to talk about."
"Yes and we'll have time to eat and lick our wounds after we get out of here." Tai said strongly. "If we have to fight that thing again, we'll need to save our strength." He looked towards the direction that Izzy said was the way to Gennai's place and started walking. Ash looked a little disturbed, he did not like being ordered around, but soon he shrugged and started following Tai.
The walk took about two hours by Sora's count. They all walked in general silence, being very low on moral. Ash seem to recover some of his strength, but being true to his gender would allow anyone to help him. The Pikachu thing seemed to recover soundly, but seemed to remain nervous about being in a strange place and napped on Ash's shoulder. In due time they came to a small cave, and began to set up camp.
True to his word, Izzy began to give Ash an abridged history of the Digidestined. He explained how they all came to this world and met their Digimon, who helped and protected them against the many hazards that they faced here. He even showed Ash their Digivices.
Ash tried to digest all of the weird information. He looked thoughtful and asked. "Are you putting me on? Your telling me that I'm not on earth, but in some strange other world?"
Sora sat down next too Ash and placed her hand on Pikachu's head and stroked its soft yellow fur. The Pikachu smiled and cooed at her that it liked this attention.
She then looked at Ash and said, "I know it seems strange, it was to all of us when we first came here, but it's all true. This is not Earth, but the Digimon."
Sora glanced at Izzy. It was often very hard you know what Izzy was thinking from moment to moment. He looked at Ash questionably and then it the Pikachu, but said nothing. Obviously, Izzy was forming some notion in his mind but, didn't seem fit to share it, yet.
Joe continued to hand out the food that he Gomamon gathered on their walk here. "But there are few things that bother me about this. First of all how did Ash get here to the Digiworld? I mean I thought only the Digidestined could travel here. So maybe if you told us about your self and the last thing you remember before you woke up here, we could it all out."
"Er.. Okay, but my story is not too special." Ash's story was special and equally confusing. He was 11 years old from the town of Pallet. Sora was pretty good with geography, but never heard of this Pallet Town, Viridian City, or Saffron City Ash has mentioned. Ash claimed to be on a "Pokemon Journey" with his friends so that one day, he would become a "Pokemon Master". Two concepts that Sora never heard before. Ash said that he went to the lab of Professor Ivy to help with an experiment with the Digital Pokemon: Porygon. There was some kind of explosion and he and Pikachu was sucked into some kind of vortex, then woke up here. Sora noticed that Izzy lessened to the story, still forming thoughts and theories, but all the while, looking sadder and sadder.
"But that doesn't explain how you got with Pikachu you must have come to the Digital world at some point. This is the only place that Digimon come from." Tai complained seeming more confused then when he started.
"What do you mean? I told you, Pikachu is a Pokemon. Everyone knows that!" Ash patted Pikachu on the head. "He was my very first Pokemon, given to me by Professor Oak himself. God don't you guys know anything? As a Pokemon Trainer, I hunt and capture other Pokemon, then raise, train and help bring out their full strength and potentials. They learn from me and I learn from them, right Pikachu?"
"Pika, Pikachu!" The Pokemon happily agreed. It was odd to Sora that the Pokemon could not speak as the Digimon did. She was more confused than ever, and from the way it looks on everyone's faces, no one seemed to understand what Ash was saying.
They sat in silence for a few second, stumped on how to proceed. Izzy jumped up and walked to the far cave wall. "Damn.." said with his teeth clenched together. "DAMN IT, DAMN IT, DAMN IT!" He yelled out with his face in a mixture of anger and remorse. Sora had never heard Izzy turned to Ash with his eyes deep with sorrow and said, "Ash, I am so sorry, you came here, because..." He trailed off, unable to continue.
"Because why?" Ash asked curiously.
Izzy hesitated then said, "Because there's no way for you to get back." He finished while setting down with his back to the wall seeming totally defeated.
"What do you mean he can't get back? We can travel back and forth between Earth and the Digiword and as soon as we take care of Demonicamon, we'll just bring him back with us." Tai said. Sora had to agree it seemed reasonable to her that they should be able to take Ash back home. Then put him on a plane to wherever this place:Pallet Town was. Something about Izzy's expression told her it would not be so easy.
Izzy face did not change as he merely said, "That would be true if Ash was from earth, but he's not from earth, at least not our earth."
"What are you talking about now? If he's not from Earth, where else would he be from!" Matt yelled angrily.
Izzy then ignored him and went back to the raven haired boy. "Ash, you were talking as if everyone knew about Pokemon, is that true?
"Of course it is, Pokemon are in every part of our culture." Ash said confused as Sora was at the moment.
"No Ash, Pokemon are in every part of your culture, not ours." Izzy said almost sub-vocally. "Ash is from a totally different world, no a different universe then we are. In our universe, the only "Mon" that exist here is the digital world. And only a handful of people know about it, but in Ash's world world, "Pokemon" are known and expected as part of his world. The Digital world, the Pokemon world and our Earth, all three different realities." Izzy said with profound sadness. " And now Ash was pulled away from his friends and family, and there is no way for him to return and it's my fault."
Tai rubbed his chin and said, "Okay let's just say that he is from another world, then how did he get here?"
"Ash said he was in a laboratory helping with a Digital Pokemon project, and that there was an explosion. I'm assuming that some quantom based energy was being used, right Ash?", Izzy asked.
"Yeah, I remembered Professor Ivy said something about quantum energy."Ash replied.
Izzy continued, "That overload of quantum energy, punched a hole in the space/time. While at the same moment, the Digital Gate I made to destroy Demonicamon overloaded and imploded. These two quantum events, combined to make a vortex from Ash's world to the Digiworld."
Usually Sora could not grasp all of Izzy's theories, but she understood this one except for one thing, "Okay I think I get all of that, but why can't you just make another digital gate and send him back to his world?" Sora asked.
Izzy just shook his head and said. "Not impossible. Ash just being here proves the "Multiple Universe Theory", basically there would be an infinitive number of alternate realities, each with it's own quantum signature or vibration. Without knowing the exact same quantum signature of Ash's world, we can search from now till the next thousand years and never find his."
Ash stomped his foot angrily. "NO! You can't tell me that. If there is a way here then there is a way back. Just because you think it's impossible doesn't mean we can just give up. I'll never give up getting back to my home." Ash said defiantly.
Sora then saw Matt leaned against the cave wall and fold his arms. "Humph! Maybe you better let him give up; it could be safer for all of us. Look at what Izzy's theories have done so far." Sora winced at that cutting remark, Izzy felt bad enough without Matt making him feel worse. Sora began to walk over to Izzy to try and comfort him, but it was too late. His cruel words words hit their mark and Izzy's tears started to flow.
Sora became instantly angry at Matt. She knew he could be hard at times, but he has gotten too far. Much to Sora's surprise, Ash jumped to Izzy's defense. "Hey lay off him!" Ash faced the hot-headed digi-destined angrily. The blonde headed boy glared at Ash with his temper now getting out of hand. "Look who are you to tell me how to talk to my friend. This is none of your business so stay out of it, kid!" He finished with a snarl.
The both of them walked to each other and stared into each others eyes angrily. 
"Now that I'm here it is my business! Izzy is doing the best he can! I'm sure whatever he did, he didn't mean to! Now for the last time..LAY OF HIM!" Ash screamed.
Tai rushed up to to attempt to stop this fight before it gets out of hand. "Come on guys, lets just try to be co..."
"YOU STAY OUT OF THIS!" The two of them yelled together.
Sora hated this because she knew how boys were, and soon the two boys began to push and shove each other. Before any punches could be thrown,a small ball dropped off of Ash's belt. The red and white ball hit the ground and bounced a few times. The Digidestined were getting confused of what was happening. Then popped open a flash of white light that made everyone( besides Ash) startled a bit. The light faded and another Pokemon appeared. 
"Bulbasaur!" It said a little disoriented. "Oh, with everything that's been going on, I forgot to see if my other Pokemon are alright." He then began to count the red and white balls around his waste.
Sora was a little shocked. It never occurred to her that Ash would have other Pokemon besides cute little Pikachu. The second one was green with a flower bulb on his back. Sora almost giggled, when she put the flower bulb with it's name. Bulbasaur, it made weird sense. Sora watched as Pikachu went down to him and explained to what was this place.
"Pika, pika pika pikachu!" he said to the new comer.
"Bulbasaur, bulba, bulbasaur, saur, bulba!" it replied.
"Weird that all they can say is their names." Sora told Biyomon. "I wonder why they can't talk?"
Biyomon flew forward and hovered above Sora. "But they can talk Sora. I can understand them."
Agumon added, "Yeah, Pikachu is telling Bulbasaur how he and Ash came to the Digiworld world.
"Humph! Bulba bulba saur..." The green Pokemon said with a small sneer.
Pikachu started to giggle a bit and so did the Digimon. They all seem to share a joke that the humans were left out on. "I wonder what he said that was so funny?" Mimi spoke up.
"Oh you wouldn't get it Mimi." Palmon said with a slight smile.
Bulbasaur seem to hear Palmon then turned to examine her. "Bulbasaur!" It said with a crooked grin. Bulbasaur walked over toward Mimi and Palmon. Its eye tracing Palmon up and down, while it walked around her. "Bulba bulbasaur bulbasaur saur bulba saur saur." It said leering at Palmon. She answered blushing profusely. Sora didn't think anything with green skin could blush, but whatever Bulbasaur said did the trick. Which only cause all other Digimon and Pikachu fall over in laughter.
With all that transpiring, Sora almost missed Izzy picking up the small ball. Izzy looked it over and the beginnings of a grin formed on his face, "Err.. Ash, what is this and how does it work?" Izzy asked while holding up the ball.
"Well." Ash began rubbing the back of his head showing that he was not too sure. "It's a Poke Ball, it's used to capture and store Pokemon. All I really know is what Professor Ivy told me, but she said something about a quantum matrix and something called photons. I only use them, I don't really understand them."
Izzy smiled. "Now I understand it enough of it, the Quantum Matrix was all I needed to know. Your Pokeball maybe the key of getting you home, but I'm not sure yet. I need to do some research and talk with Gennai."
Ash's curiously peeked asked, "How can my Poke Ball get me home?"
Izzy just smiled and said "I don't know if I can, but it might. Your Poke Ball has a Quantum Matrix that may have the quantum signiture of your home. Just give some time and you'll be home as soon as possible."
Ash walked over to Izzy and placed a friendly hand on his shoulder. "If it does or not, thank you for giving up on me Izzy." Izzy and Ash exchanged smiles and mood of the group had been lightening. One problem was being worked on, and that problem was Demonicamon still haunting them.
The rest of the night was not uneventful, given renewed hope of getting home. Ash began to speak with all of the Digimon. Ash seemed to love everything about them, Sora thought he looked like a kid in a candy store, wanting to touch everything he sees. He used his Pokedex to look up their then noticed the Digimon showing off their attacks to the new person. After seeing Ash's sense of wonder it made Sora think.
Before she began to settle down for a nights sleep, she took Biyomon in her arms and said, "I love you Biyomon, and thanks for everything you did." She glancd at a yawning Mimi and Palmon sleeping next to each other. She also saw Ash's Bulbasaur slept next to Palmon.
She then saw Ash studying a sleeping Agumon. He looked terribly weakened from the events of today. At this rate, he would be in no condition on the road to Gennai's tomorrow. She stood from her bedroll and walked over to him.
"Ash your going yo wear yourself out, get some sleep." She whispered in his ear."
His sleepy eyes focused on Sora. "Oh I'll sleep in a little while, I just need to get a few more measurements from Agumon here." Sora shook her head. Ash was dead on his feet. She didn't want him to be so tired, so she did what she had to do. Sora took hold of Ash's ear, causing a small pain, and lead/force him to the spot she was sleeping. "Ow! Sora, what are you doing?"
"If you won't go to bed, I'll put you to bed." Sora said sternly. "Now take off your hat and jacket, and do it quickly or I might decide to make you take off your pants too." Sora finished with evil grin, enjoying this very much. Ash tried to protest a firm pinch on the ear, Sora continued holding settled that. She watched as Ash laid down next to her bedroll.
Then Ash sat back up and said, "Let me just scan an image of Gatomon's tail ring and I'll.." Sora decided to put an end to it once and for all. She quickly climbed on top of Ash, straddling his waist; she put her hands on his shoulders and push him back down to his back.
"Ash Ketchum, stop being so stubborn! Now lay down and get some sleep!" Sora told him sternly. Ash seemed shocked at her forceful action and his eyes widened displayed in surprise. Sora looked into his eyes, as Ash seemed to study her, Ash's eyes traced every inch of her face as if she was something only he could look in his eye and a subtle change of expression took Sora a bit back. "What?" was all she could ask.
Ash's smile and eyes became warm, and his face softened, "The way you said my name just now, you just reminded me of someone." Ash's hand reached up and held the side of her face; his touch was caring but did not hide the sadness he seemed to feel. Sora's heart melted and her skin tingled. "I'm sorry Sora, I know you're looking out for me. I'll go to sleep, thank you for caring." Ash told her with a smile. Sora then became quite aware, of the position they were in.
Sora blushed and climbed off of him and lie down on her bedroll. Ash closed his eyes and quickly fell asleep. It was a full and disturbing day, and the weird feeling she received from Ash's touch would turn this into a disturbing night for her. She closed her eyes and drifted off into strange dreams, with the hope that the Digidestined, and their new friend Ash would some how be able to face the challenges that awaited tomorrow.