Killing Zouken

"Zouken...!" Kariya didn't even bother addressing the man formally anymore as he glared at the bastard with killing intent. These eyes made the old monster frown as he found it displeasing to see.

"You think you're worthy of addressing me by my name?" As the oldest and respected member of the Matou Family, he found the arrogance of his descent to be something he had to fix right away.

"We're leaving." The way he stood up to the old monster caused the young girl in his arms to latch tighter to his body in fear. She was scared that her Grandfather would kill her Uncle like before.

Sakura didn't want to lose him again...!

"You failed to bring the Holy Grail, so the deal is-"

"Who cares about a deal?! She's leaving with me and that's final!!!" The purple-haired man roared.

It was at this point that the Blade Wing Hollow Worms hidden within his body started to pour out of body in large amounts. Even the old monster widened his eyes as the amount of bugs pouring out of him made it hard to see the ceiling.

"What impressive yet crude...! Looks like you're not as incompetent as I thought you were." The old man smiled. Even though he didn't have the chance to hide his 'main body', he was confident he could deal with someone who wasn't a Servant.

"Sakura-chan, hide in that corner. Your Uncle will come back for you, I swear." These words caused the young girl to nod her head obediently as he lowered her to the ground. Even if he had a new sword-like Mystic Code, he was a insect user.

The fight between the Matou were mid-ranged.

He commanded the Blade Wing Hollow Worms that were a level stronger than the ones he used when he was alive, commanding them to rip his ancestor to shreds! However, Zouken had seen this coming.

"A pity..." The old monster spoke as his bald head and right side of his body transformed into Crest Worms. Similar Blade Wing Crest Worms attacked their more powerful counterparts, and obviously ended up being the ones which were losing out.

However, his great mastery over the Blade Wing Crest Worms wasn't to be underestimated as he was able to injure quite a number of them, which opened up the opportunity for him to personally attack them, as his Blood Worms siphoned energy.

A fusion between the Absorption Spell and the Matou Family's ancestral Magecraft allowed him to temporarily hold his own against the swarms of Blade Wing Hollow Worms. Not that his struggles were enough to change the battle's outcome.

'Die like a pig!' Kariya's eyes flowed red as he threw 9,000 Hollow Worms to attack Zouken while only using what were left to defend Sakura and himself from harm. He was no longer a glass cannon, and his quantify of insects beat Zouken's 'quality'.

"You leave me no choice!" The old monster knew he would die a useless death if this went on any longer as the Hollow Worms weren't giving him time to escape. The strange magical energy he was taking from the Blade Wing Hollow Worms allowed him to 'regenerate' by maturing more Crest Worms to fight at a faster rate, but the damage he was taking exceeded the amount of Worms being killed.

He had no choice as he brought out an eerie box covered in a miasmic aura of corruption and swallowed it whole. The tainted Grail Shards he had collected specifically to turn Sakura into a second Lesser Grail were used to enhance him.

He didn't want to die! He wanted to attain immortality even if he turned into a Wraith!

For he was the last of the Makiri Family to have researched Spells beyond what others knew of.

The Giant Worms created from humans who had been thrown into the Bug Pit heard his call and attacked the Hollow Worms that were surrounding Zouken. Their chitinous and spider-like bodies as big as cars rammed into the swarm before being converted into more Blade Wing Crest Worms. A sense of fatigue started to overcome Kariya...

The battle was long and hard as Zouken turned into a demonic figure with near limitless magical energy momentarily after swallowing the Grail Shards, defeating all 9000 Hollow Worms in the process. Then he started approaching Kariya.

He checked out his own condition before realising the bug that was his 'main body' was overloading from the corrupted magical energy from the Grail Shards. It drove him to near insanity that his incomplete descendant brought him to near death.

He couldn't 'regenerate' anymore.

"If I'm going to die, you're coming with me!" The bald freak reached out to devour Kariya whole.

The Blood Worms desired nourishment, and even the Hollow Worms left to protect him weren't able to stop him as he pursued his target with the intention of using what's left of his life to 'devour'.

The purple-haired man roared as he attacked Zouken with Arondight. His sword heavily slashed down to chop him in half. It was too bad that his movements were sloppy as someone who had never fought before, allowing the more experienced old monster to parry the sword with his wooden cane before hitting the man's head.

The hoodie Kariya wore acted as a helmet protecting his head as Zouken attacked him, but this much wouldn't be enough as the Blood Worms tried to enter his body and drain him of his blood.

Little did the old monster realise that devouring the Grail Shards was his worst mistake. Even someone who wasn't as well-versed in magic like Kariya realised something was off about the Crest Worm that acted as his 'main body' while being attacked.

'This time I WILL save her from this hell!' Even as his blood was being drained, Kariya managed to use the strong willpower he had cultivated over the Holy Grail War to reach out to the 'main body' of his ancestor to use the family's Absorption Spell.

"W-what?! How?!!!" Zouken was shocked as the strength of the Spell was so much stronger than anything he had taught. This factored in with the difference in size between their vessels to make him unable to resist being 'swallowed' by the Spell.

He roared in anguish as even his corrupted soul and body infected by the Grail Shard were absorbed into Kariya's body, allowing him to forcibly seize the memories of his 'Grandfather'.

He felt his mind and body being corrupted by the taint of the two evil influences from top to bottom.

"Uncle Kariya...?" The purple-haired man didn't answer for a while as he took in the memories.

[You have acquired the Makiri's Secrets 'Gu Research' along with Makiri Zolgen's personal research into immortality. Your Magecraft has improved and you have attained new Spells.]

[You have acquired the Matou Family's 'Crest Worm' Magic Crest, attaining the research and Spells of the previous Matou Successors. Your Absorption Spell has reached a new limit.]

[Beast Hollow within you has acquired the Black Blessing 'Blessing of the Darkness' Skill and the Polluted Hollowfication 'Spiritual Contamination' Skill... Warning! The Skill 'Connection to the Root' is interfering with the System... It is advised to not confront the Beast Hollow within or else risk being endangered... Emergency protocols are active...]

After finishing, the 100 Blade Wing Hollow Worms returned to his body as he knelt onto the floor. The combat form he was in deactivated as his tracksuit became less of an armour and more like clothes.

He took off his hoodie and wrapped his jacket around Sakura before bringing her out, letting her have a taste of freedom she always deserved. It was only after getting outside the mansion did he stop to think about what he would do next.

"Uncle Kariya, where are we going now?" The young girl's innocent words made him think.

The mental strain he had gone through tonight made it so the moment he relaxed, he wasn't able to resist the urge to sleep. Finally, they were free to do whatever they pleased now Zouken was gone.

"I'll... take you... to see... Rin-chan." Was what he intended before being unable to stop himself from falling asleep. The sword Mystic Code had vanished and he was left with nothing to defend himself with other than the 100 Hollow Worms.

Sakura looked at the moon and was unable to believe if what she was experiencing was reality or a dream she cooked up for the sake of protecting her heart. Could it be the real her was still being tortured in the Worm Pit like every other day?

Regardless, she felt tired as well as she snuggled up to the man who saved her and fell asleep too.

The next day was one where Kariya decided to think more realistically about what he would do from now on. With Zouken now dead, it meant that his nephew, Shinji, and his brother Byakuya, were left to hold rights over the Matou Family.

With him taking the Magic Crest of their family, he could probably pass himself off as the Successor appointed by Zouken himself. With that in mind, he used his more more intelligent mindset that had gained Zouken's experience to usurp whatever the Matou Family had to offer. He also made preparations for Sakura to reunite with her family.

'Is this the truth?!' As he was getting information using the networks Zouken had already established on his own, he came across a piece of information that made him both ecstatic and filled with despair.

Aoi Tohsaka had survived, thankfully, from his bout of madness, but her mind was no longer there after losing her husband and daughter. The dark green haired maiden was lost in her fantasies of having a family that hadn't been ruined by the Grail War.

'Aoi...' His heart ached as his once childhood friend had been driven to such a state by his own hands.

No, now that he could think more rationally and had the experience of seeing many schemes in Zouken's lifetime, he felt something was off about Tokiomi's death, and shifted through the records.

The fact that he was approached in his darkest moments by a priest made him more suspicious.

He even checked his ancestor's memories for a name until he came across information regarding that 'Executer' of the Church. Kirei Kotomine, that was the name of that priest who was part of the Holy Grail War, and his personality was...

Several different factors were considered before he came to a terrifying conclusion as he checked who was currently Rin's legal guardian. After seeing that same name pop-up, his eyes widened as he realised what had happened from the clues.

'This bastard killed Tokiomi!' The killer of her own father was now acting as Rin's legal guardian...!

He suddenly realised that there were so many things he needed to do to protect his loved ones.

'Is this why you gave me your strength?' Kariya wondered as he put his hand on his chest and thought of the Servant who had now became a part his very being. He didn't understand the Amalgam System, and he realised he couldn't even interact with it even by talking out loud. It only seemed to notify, warn, and advise his actions.

'What to do first?' He tapped his finger on the table as he was no longer rash or as naive as before.

He knew that trying to protect someone and keeping them in a fake paradise were two different concepts. Even if it would hurt Sakura to see her mother in such a state, they needed to meet if they ever hoped to reach a catharsis in their hearts.

Longing will hurt her more than suffering, he knew that well after seeing how she was able to endure the Worm Pit without screaming, which in his point of view, showed she was stronger than most.

'Where is she now?' So as to not cause suspicion in Kirei before the time was right, he quickly hatched a Spying Worm that he had created to mimic a regular fly. Although it couldn't sense magic, it could locate individuals by sending images to him.

Meanwhile, Aoi herself was becoming more and more listless as the brain damage caused by Kariya strangling her back at the church made her unable to grasp the fact that Sakura and Tokiomi were gone. She was wheelchair-bound and was unable to move around without Rin's assistance. These images of them suffering caused him to anguish.

"Uncle Kariya, will I be able to see Mommy?" The light was slowly returning to Sakura's eyes as she became much more energetic. He didn't leave her alone for too long and always made sure to see her for at least six to seven hours after they woke up.

He didn't want her to feel isolated, and let her lay her body on the sofa as he was going through the paperwork of a family head. He made sure to hide his horror of his findings using a piece of paper as he was going through many things at once.

"Tomorrow you'll get to see her Mom, okay?" He forced himself to smile confidently towards her.

"But I'm going to need to prepare some things on my own first. Are you okay staying here for a little longer?" He asked, and nodded her head before walking out after hearing someone knock on the door. Kariya watched as she left with melancholy.

"Brother..." His older brother Kariya called out as he closed the door behind him as she left, with eyes of a hawk he continued: "Has Grandfather really left for good? What about the Matou Family?"

"I think we can do a better job without him, don't you think so?" Kariya changed his tone as he replied with much greater firmness and authority than he did when he was in front of Sakura.

"You... Who had abandoned Magecraft, dare to think of this as a joke?!" Byakuya grabbed his little brother's collar and roared. If Zouken left then there would be nothing left of their Magecraft.

"Don't be so alarmed, Big Brother. Moreover, I'm sure you're also happy that monster isn't ruling over us after what you did." The memories he gained showed that Zouken was already aware that his 'grandson'. His brother's right hand hanging to the side, which had yet to heal, was a good indicator that he had been interrogated, and that information about him had been leaked previously.

Byakuya started shaking in fear as the current Kariya no longer seemed like the little brother he knew. The purple-haired 'stranger' took the left hand holding his collar off before continuing:

"I won't ask who came for you. Me being part of the Holy War is something that put you in danger regardless of what happened. I'm sorry... I want to make it up to you." He spoke in a deceptively gentle tone as he calmed his brother down.

"H-how will you make it up to me?"

"Zouken left behind a breakthrough in magical research before leaving, which is this healthy body of mine. Surely, you also know that returning to this state after being 'broken' before the war means about what I've learned, and how I can help you."

Kariya threw out some bait to latch onto the inferiority complex that had been born from Zouken calling his older brother a failure. He knew the obsessive man before him couldn't stand his inadequacies as a Magus and wanted strength.

"...You're willing to help me, even as the Matou's Successor?" He digested what he had heard.

"Of course! Only one Successor can exist in a family, but that doesn't mean we ignore training."

"I... don't have great Magic Circuits like you do."

"Neither does your son, but I promise if you help me both you and your son can gain more power."

"Using what 'remade' you...?"

"Yes!" Kariya became assertive as he persuaded his brother, who was not feeling a glint of hope.

"What do you want me to do?" Byakuya shifted gears. Nothing in this family came for free.

"Take care of the kids when I'm away. Make Sakura feel at home, and well, be a better parent, alright?"

"That's it...?" He found this suspicious.

"I don't have enough manpower since Zouken left and there's a lot for me to do. I want to put my trust in you." The purple-haired Magus finally spoke with sincerity towards his mostly estranged older brother. It was a good thing the man was realistic.

"I'll help. You can be at ease." He patted his chest.

"When I come back tonight, I'll share with you the research Zouken had been holding back on us."

"Wasn't it written down?" This 'cute' question made him narrow his eyes as he shook his head.

"It's all in here, and my blood will be needed if I want to help Shinji become a Magus like us. We can't have him growing up with just dreams in his head. Our 'family' needs to change its traditions."

Byakuya sighed as he remembered his son had an unusually strong fixation to become a Magus. He had no hope in his child before, but now he was thinking differently if his little brother could truly live up to his words. Perhaps the Matou bloodline won't die out if Kariya's absurd claims that gave him a tiny spark of hope turns out to be true.

He decided to wait it out until he saw results.