Hey guys, this will be my very first SAO fanfic. Hope you guys will be able to enjoy this.Disclaimer: I do not own any of the SAO original characters here. They belong to Reki Kawahara.

March 27th, 2027

Kazuto's POV

"Have you ever truly experienced the feeling of losing your sense of reality?" A disembodied voice echoed eerily through the darkest depths of my mind. Just who was that, I asked myself as I gradually awaken from my deep slumber. My eyes squinted as the bright light entered my sight. After adjusting to the bright white room, I looked around only to realize that I was lying on one of the STLs located in Rath's Roppongi branch. It took a moment for me to recollect my thoughts before remembering that I was logging in to the Underworld along with Alice to make sure everything is going smoothly. Normally, Asuna would have joined us on these visits but she already had an appointment with her family today and couldn't make it.

These trips were also the opportunity for Alice to reunite with her precious little sister, Selka. Even after more than 200 years had passed in the Underworld, Selka still remained. She had decided to keep herself in a deep freeze state until Alice returns. During Alice's visits, Selka would spend quality time with her beloved sister and returned to her stasis state when Alice leaves for the time being.

The people of Underworld were living peacefully and had already started developing new Sacred Arts on their own to make their lives much easier. Although, I didn't have any recollection of my contribution in its advancement during my 200 years being stuck in Underworld along with Asuna, but seeing Underworld safe from destruction was more than enough. However, a part of me actually wished the people I once knew in the Underworld, could have lived until this day to witness this scene. Every time I thought about them, I would feel a sharp pain in my chest, especially when I think about a certain flaxen-haired boy. That boy who sacrificed himself for me, for the people he loved and for this world. Yes, my best friend, Eugeo, whom I've shared 2 years of my life in Underworld with.

Shaking off the depressing mood, I sat up from the STL and was getting ready to leave the building. Alice had decided to extend her stay in Underworld for a few more days with Selka before returning to the Real World, so I left Underworld alone. As my feet touched the cold floor, I felt a small wave of light-headedness which almost made me lose my balance. I assumed that it might have been due to the hectic schedule I had these few days and thought that I should get home and rest up early. As I stepped out of the building, immediately my phone rang with the caller name, "Yuuki Asuna", listed on the screen. Seeing the name of my lover made me smile, as I happily answered her call while walking towards my motorcycle.

"Hey, Asu-"

"Kirito-kun, are you okay?!" A loud frantic voice came from my phone, surprising me as I pulled the phone away from my ear.

"W-what's wrong, Asuna? What do you mean? I-I'm fine. I was just about to head back from Rath." I answered nervously.

"Are you sure you're okay? I was watching the biosensor app when I saw that your heart rate spiked for a moment and I thought something might have happ-" Hearing Asuna's distressed voice, I quickly intercepted her.

"A-Asuna, I'm fine. Really. Don't worry, okay? A-anyway, are you back from your trip to Kyoto already? You're going to the meetup tomorrow, right?" I chuckled nervously and changed the subject.

"Geez, don't scare me like that, Kirito-kun. I just reached home a while ago and, of course, I'm going tomorrow. Wouldn't miss it for the world. Besides, I missed seeing your face." Asuna's tone immediately softens at the last sentence.

"Yeah, I missed you too. Couldn't wait for tomorrow." I couldn't help but to smile at that sweet voice of hers. "I'm heading back home now, so I guess we'll talk more tomorrow then. Love you."

"Okay. Drive safe, Kirito-kun. See you tomorrow. Love you too." I hit the end call button after Asuna finished and put on my helmet before riding back home.

Normal POV

Kirigaya Residence

It took almost about an hour before Kazuto reached home on his motorcycle. The journey was getting rough for Kazuto as he felt his dizziness getting worse along the way. Kazuto parked his motorcycle in one corner of the driveway and got off ride with a heavy sigh.

"Am I really that exhausted? Guess I'm gonna need to head off to bed really early today." Kazuto mumbled to himself as he headed over to the main entrance of the house.

"I'm home!" Kazuto yelled upon entering the house. As he was taking off his shoes at the entranceway, Suguha happily skipped from the kitchen to the corridor and welcomed her brother home.

"Welcome back, Onii-chan! I'm just about to prepare dinner. You can take a shower first while you wait."

"A-ah, about that." Kazuto rubbed his head apologetically. "I'm not feeling too good today, so I think I'm gonna skip out on dinner. Gonna head off to bed after taking a shower."

"Oh, I see." Suguha's smile turned into a concerned frown. "Are you sick? Are you sure you can join the meetup tomorrow? If you're not feeling up to it, I can let the others know and postponed it to another day." Suguha asked worriedly.

"Nah, it's fine. I'm sure I'll be back to myself after a good long rest. Don't worry, kay?" Kazuto ensured Suguha. With a gentle pat to her head and a comforting smile, Suguha returned with a small smile before watching her brother slowly walk up the stairs.

Later that midnight

The Kirigaya Residence was enveloped in total darkness as everyone was already sleeping soundly in their respective rooms. However, that could not be the same for Kazuto. Despite tucking himself in early, the peaceful slumber he had wished for never came. His head was drenched in cold sweat as he tossed and turned in his twin bed. His breathing became ragged but his eyes remained closed as if he was trapped in the depths of his nightmare. Inside his mind, all he could see was the people he had killed and the people he couldn't save back in the SAO era. Even the faces of those whose lives were sacrificed in Underworld appeared, endlessly reprimanding him, blaming him and taunting him for their deaths. In his mind, Kazuto had both hands holding his, covering his ears and shutting his eyes tightly, desperately trying to block out the voices and images surrounding him.

"Not this again. Please...stop...I beg you." He pleaded with a weak shaking voice, but the horror continued throughout the night, not allowing him any peace of mind. The struggle continued till the extreme exhaustion finally hit him, causing him to faint in his sleep.

As morning came, a gentle knock came from the door of Kazuto's bedroom. It was already 10 in the morning and their meetup was supposed to be half an hour before noon, yet Kazuto did not wake up. Suguha thought he might have overslept again and went to his door to wake him.

"Onii-chan, wake up. We're gonna be late. You need to get ready and eat your breakfast." After a few knocks without response, she decided to enter his bedroom only to find her brother still on the bed. Suguha frowned and was about to pull on his blanket, but what stopped her was that she felt something was out of place. Kazuto has always been a heavy sleeper, but he was definitely not the type to move around too much while sleeping. Currently, Kazuto's bed was a mess. The blanket had fallen onto the cold floor and his pillow was all the way across the room. Suguha carefully walked to his bed and saw her brother curled up on his side with knees tucked into his chest. There were signs of him sweating throughout the night as his bangs were in clumps and slightly damp.

"Onii-chan, are you okay?" Suguha lightly placed her hand on her brother's shoulder and gently shook him, trying to wake him up. However, there was no response. She looked to the bedhead where his phone was located and softly called. "Yui-chan? You there?"

The screen lighted up as a small yawn came from the phone. It was the voice of Kirito and Asuna's beloved daughter, Yui, who is also a top-down AI. "Good morning, Leafa-san. Is there something wrong?"

"Yui-chan, have you noticed anything wrong with Onii-chan last night?" Suguha asked in a small voice.

"No, I did not. I was also asleep the whole time Daddy was asleep." Yui replied, leaving Suguha to wonder what happened last night. "But, yesterday evening Daddy received a call from Mommy. She was also worried about Daddy, saying that his heart rate spiked for a short moment." Yui added.

"But what does that mean?" Suguha was even more confused.

Worried that he might be ill, she gently placed her palm on his forehead to feel his temperature. Kazuto's skin was cold and slightly sticky from sweat, not hot to the touch as the younger teen had expected.

''It's not a fever, I think. But still, he feels so cold and it seems like he was sweating a lot last night." Just as Suguha finished her sentence, a small grunt came from the boy as he began to stir. He slowly opened his eye and blinked as his vision gradually clears up.

"Sugu..."His voice sounded hoarse and dry. "What time is it?"

"It's 10.30 already." Suguha answered as she watched Kazuto slowly rose from his bed.

"Already?" Kazuto groggily looked around his bedroom, finally noticing the mess. "What happened here? Did I do tha-arghh!" Kazuto yelped and clutched his head with his left hand as a sharp pain shot through his head.

"Onii-chan?!" "Daddy?!" Both girls yelled in concern at Kazuto's pained expression.

"I'm fine. Just a bit of a headache. That's all." The teen assured them as the pain subsided. "Probably didn't sleep well last night. Must be some heck of a nightmare that I can't even remember what was it about."

"Hey, Onii-chan, maybe you should stay in bed and rest up. You seemed really pale. I could tell the others to postpone the meetup." Suguha said to Kazuto and was about to get her phone to contact the gang, but Kazuto stopped her before she could.

"There's no need to cancel the meetup. I'm okay. Promise." Kazuto gave Suguha the biggest smile he could muster to convince her that he was alright. The younger teen gave in and sighed.

"If you say so. If we're going then you better hurry up and get ready. It's late. I'll make the bed for you." Suguha said as she shoved Kazuto out of bed and towards the door.

"Yeah. Yeah." Kazuto lazily grabbed his towel and headed to the bathroom with a loud yawn.

Ensuring Kazuto had closed the door behind him, Suguha turned to Kazuto's phone with a worried expression. "We should talk to Asuna-san about this. This doesn't seem right."

"I agree too, Leafa-san. I'm worried about Daddy as well." Yui replied.

It wasn't long until Kazuto had showered and returned to his room for a change of clothes with his damp towel hung over his shoulder. He took off his pyjamas and grabbed a pale blue dress shirt with a matching pair of black trousers from his closet. The black-haired teen scanned his closet once more before deciding to put on his blue cardigan as the weather is still quite cold in the early spring. Grabbing his sling backpack, Kazuto took the Augma device from his desk and placed it into the bag. Looking out the window, he noticed a black figure standing across the streets look back at him with a sinister grin. Kazuto couldn't make out the face, but he felt a chill down his spine. A trail of cold sweat dripped from his head as he felt the familiar sense of fear during his days in SAO. He felt a throb in his head once again and closed his eyes, trying to get rid of the pain as he gently shook his head. Once the pain subsided, he opened his eyes to find the figure missing. 'Am I imagining things?' Kazuto thought inwardly.

"Daddy?" A small voice came from his phone, sounding worried.

"Huh? Yui? It's alright. It's nothing." Kazuto reassured his in-game daughter with a small smile. Just then, a yell came from below.

"Ka-zu-to Onii-channnnn! Your breakfast is getting cold. Hurry up. We're going to be late!" His sister yelled from the bottom of the stairs in an annoyed tone.

"Crap! I'm coming!" Kazuto answered and grab his phone before heading to the dining area.

After breakfast, the two siblings put on their shoes and step into the driveway. Kazuto instinctively began walking towards his motorcycle.

"Urghh!" The black-haired boy immediately felt a tug at his sling backpack as he was trying to do so, nearly choking himself. "W-what is it?" The boy turned to his sister with a troubled look.

"You're not planning on riding the motorcycle, aren't you?" The sister asked with an angry look.

"Well, how do you suppose we go then?" The elder sibling retorted.

"You're not feeling 100% and you have a headache. So, we're either taking the cab or the bus, are we clear?" Suguha threatened her brother, bending forward with one hand on her hips and the other pointing at Kazuto with her angry face brought close to his. With a heavy sigh, Kazuto can only comply with his sister's demands and the two walked out of the house and ordered a cab.

That's it for Chapter 1. I can't guarantee a consistent upload of new chapters as I have work. So, hope you guys can continue to support me and stay tuned. Comments and positive criticism are most welcomed. :)