Eiro pushed his hand forward, conjuring a compressed stream of the hottest flames he could bring forth. Everything around Merlin was being singed, except this old man himself.
Merlin waved his hand around and once more created a mass of arcane magic. He didn't seem to have a wand on him, so Eiro was at a light advantage, at least. The arcane magic was still able to fend off Eiro quite a bit, however. Now, instead of turning into something like ropes to hold him down, the arcane magic turned into a bubble that surrounded the Demon, entrapping him.
Slowly but surely, the bubble was shrinking, "It is a shame that it came to this, Eiro. I will express my condolences to your children soon, do not worry."
Eiro growled, not caring for anything that Merlin was saying. He pressed his hand forward, and pulled out as a huge amount of flames out of the planar gateway. Eiro compressed it into a tiny spot in front of his finger, and started twisting and turning it as quickly as he could. The air inside of this bubble soon caught fire itself, and turned into a raging tornado while the bubble kept on shrinking.
But when the Demon pressed the tiny spot of flames onto this mass of arcane magic, the barrier shattered into pieces as if it had been made of glass. After all, Eiro used half of his mana to create it. And he didn't just use simple flames, but he infused them with his Counter-Spell Creation skill. He created flames that were specifically targeted to destroying spells, and nothing else.
They were probably unable to singe even hair at this point, since Eiro's will made sure that they could only affect magic, strengthening the ability they had in that regard. Eiro rushed forward again with all his might before Merlin was even able to realize the barrier around the Demon had shattered, and pressed the tiny spot of flames into his abdomen.
As the protective, magical skin around Merlin shattered into pieces, Eiro pressed his fingers onto the mage's skin. His fingernails bore into his flesh, and Eiro stared into Merlin's eyes as damage notifications finally appeared in front of him.
"I really, really didn't want to do this..." Eiro said, pressing his teeth together as him and Merlin locked eyes with each other, "But I despise what you did in this place. I despise that you act in disregard for those around you out of your own selfishness. I despise those things in myself as well, but at least I'm trying to change."
Eiro's fingers slowly pushed deeper into Merlin's chest, slipping past his bones and wrapping around his heart. With clean cuts and swift movements, Eiro pulled the heart from Merlin's body. It was the quickest way to make sure he was dead right now. The body's mana core was practically fused to the heart for the creatures that had one, so no matter what he did next, this would at least slow down his mana-production.
And as the soul fell apart around that place, the mana production within him would halt completely and forever. No matter what he did then, he would inevitably die.
Blood poured out of Merlin's mouth as he clutched his chest, and he gasped for air, "Y-You... How did you..."
"Shut it." Eiro said as he kicked Merlin's stomach, really just letting out his anger at this point. He noticed that Merlin managed to prolong his life for a while by creating a fake heart using arcane magic. He stared back at Eiro, and held his hand forward, attempting to cast another spell.
"Just stop it already, both of us know that this is useless. You're going to die." Eiro said bluntly, as he crushed Merlin's heart in his hand. Eiro turned his head, glaring at Gabria. She had fallen to the ground in fear after witnessing Eiro's true form as well as the fight between these two.
Of course, the guards outside the room were alerted by what was happening rather quickly as well, but Bavet was already taking care of that. He had transformed into Eiro's 'Person' form, and made sure to hold the guards off from coming inside.
Eiro held his hands to his throat as the realisation of what just happened caught up to him, "I really, really didn't want to have to do this, Merlin! You're part of my family, you-"
"Part of your family..?" Merlin asked with a wry smile, "Hah, as if! I don't care what you say, but you will never be a part of this 'family'. You never were, and will never be Jura's son! You forced your way into his life, and you forced your way in mine! If you had stayed away, then everything would have been fine! I could have finally grown stronger, and I could have proven that I really am a master! This ridiculous system simply held me off from truly being able to say so!" Merlin yelled out.
Eiro stared back at Merlin, "...What have you been doing to the children of the academy? That girl from the other day... She was completely horrified..."
"Girl? What gir- Ah, that little brat! I simply did what I had to to make sure that she would learn her place, that nasty girl!" Merlin exclaimed, "I-"
"Just stop, I can piece it together..." Eiro grumbled, truly disgusted to his core, "Is that why you destroyed that one's village?" The Demon asked, pointing at Gabria, "The girl... She had a slight amount of Monster blood in her. Barely noticeable, the only way it must have surfaced is... her talent, maybe! A healthy appetite for meat? How can it be that you despise monsters so much you would eradicate a whole village of monster-person hybrids, but then teamed up with a fucking royal?!"
Merlin glared back for a moment, and then couldn't help himself but laugh, "You think I hate monsters?! Hah! Haha!" Eiro stared back confused, when he realised what was going on, "I hate people, you fool! Monsters are... they are perfect! Even if a creature is limited by their fate, if they kill enough, they will be set free. They will evolve, they will widen their limits, they will... become even more perfect!" Merlin exclaimed with a disgustingly excited expression.
"Of course, I don't hate all people! I truly loved Jura as if he was my real brother, even when he stopped visiting me all that time ago... And at the same time, I don't blindly love monsters... Especially those that aren't true monsters... Those people that hold the blood of monsters, those disgusting creations that defy all that makes monsters wonderful... And you, a creature who was born as a truly perfect being, you could have become the pinnacle of perfection! But you... you chose to abandon everything!" Merlin yelled out, deeply glaring at Eiro. It took him a while to realize what just happened, but when he did, he was taken aback. Still in pain, he pressed his back against the wall behind him.
"Wh-Why did I just... Just say that..?" Merlin asked, and Eiro just shrugged, "It's easy to push a spell into you when my hand is wrapped around your heart." The Demon pointed out, "You have a surprisingly low resistance against spells affecting your mind."
Merlin glared at Eiro, and shook his head, "You know what? I guess this is it! I guess I finally don't have to pretend to want to be here anymore! This act of caring for people is finally over!" Merlin exclaimed. He gathered the mana that was left within his body, and created another mass of arcane magic that he covered his whole body with, using it to cast a slightly different spell.
The moment that it was cast, and it really only took a moment, Merlin's body fell apart into pieces, turning into glowing white birds that flew into the wall, and immediately disappeared.
"Nelli, follow him please, and tell me what he does. The moment you notice danger, come back." The Demon said to the Naiad, as he slowly turned around and approached Bavet. He was still trying to hold off the Guards by pushing the door closed, and Eiro simply walked into Bavet's back and fused with him, letting the slime transform his body immediately while they were out of the guards' view for a moment.
Eiro glared at them, in an incredibly bad mood, "Give a report to the King. Merlin was one of the perpetrators of the attack that that the academy received last year, committing high-treason against not only this country but all people, by siding with the Monster King."
