For Rozen, what filled the original's heart at first was naturally anger, but more so an endless hatred.
Because, the human before her had not only prevented her resurrection but also seized her Beast Vassals, making them Rozen's property, no longer loyal to her.
The original could feel that her control over the Beast Vassals was completely gone.
In the past, even though the Beast Vassals had separated from her body and became individual entities, she still held control over them and could reabsorb them, making them return to her.
That's why they were called the Beast Vassals of the Fourth Primogenitor, and not someone else's Beast Vassals.
But this time, things were different.
At some unknown point, the original's control over the Beast Vassals had one by one disappeared, and they had formed contracts with Rozen.
From that moment on, they were no longer the Beast Vassals of the Fourth Primogenitor, but Rozen's.
On top of that, Rozen had sealed her within his body, preventing her resurrection while using her powers. Whenever Rozen unlocked a part of the seal, her power would be forcibly taken and used by Rozen, deepening the original's hatred towards him.
Therefore, whenever there was even the slightest chance, she would madly attempt to take over Rozen's body, trying to lead him into ruin.
But now, Rozen was even planning to take away her power.
How could she possibly tolerate that?
"Bang!"
The black wings behind Rozen turned into blade-like edges that sliced toward Rozen, obscuring the sky.
"Clang! Clang! Clang! Clang! Clang...!"
Unfortunately, all the black wings that landed on Rozen were deflected by shimmering runes and patterns, unable to harm him in the slightest.
Rozen merely sneered at the original.
Meanwhile, the original's attacks grew weaker and weaker.
There was no other choice.
As her mana was gradually being drained, the original couldn't unleash much power, and naturally, her strength diminished.
"Stop...! Stop it...!"
The original roared in both anger and terror, unable to accept the fate that was drawing near, struggling frantically.
"This is quite unsightly," Rozen said without a trace of pity. "No matter what, you are still the Fourth Primogenitor. Even if you can't accept your fate with grace, don't embarrass yourself too much. How else could you live up to your identity?"
"You...!" The original's face immediately twisted.
But deep down, she knew very well that continuing to struggle was futile.
So, the original glared at Rozen with eyes full of fury.
"You've taken my beast vassals, deprived me of my chance to be reborn, and now you're trying to take my power. Just how far are you planning to go?"
The original's hatred poured out without any reservation.
But Rozen remained unfazed.
"Since you've been inside my body this whole time, you should understand, this was an accident. Even I didn't expect the new magic circuit to be so overbearing, but on second thought, it makes sense."
After all, this magic circuit spread throughout every part of Rozen's body, even down to the individual cells. Since the original was inside him, it was impossible for her not to be affected.
On top of that, this magic circuit could operate autonomously, generating and refining mana on its own. If it detected any mana inside Rozen's body, it would naturally take it in for refining, right?
And while the original's power was indeed immense, her mana was still ordinary, incomparable to High-Grade Mana.
Therefore, being assimilated and absorbed was only natural.
Had the original not been sealed, she might have been able to control her mana and prevent it from being taken.
But the issue was that she was sealed, with her power reduced to a mere fraction. Furthermore, the seal placed by Rozen was designed to forcefully draw her mana for his own use. As a result, the magic circuit autonomously operated and, taking advantage of this mechanism, seized the original's mana.
Now, the fourth primogenitor's massive mana, which once surpassed even the ley lines, was steadily becoming a part of Rozen's High-Grade Mana, increasing his strength.
In other words, the original was not merely sealed anymore; her power was being stolen by Rozen.
From this point forward, Rozen no longer needed to unseal her to forcibly use the Fourth Primogenitor's mana.
Because that mana was becoming his own.
"This is karmic justice, isn't it?" Rozen said, "Your mana was originally obtained by hijacking human memories during the Flaming Banquet ritual. Now it's my turn to hijack your power. It's just a case of poetic retribution."
Thus, the original had no right to resent Rozen.
"As for your Beast Vassals, they never wanted to serve you in the first place. Now they've all formed contracts with me. Your chance of resurrection is laughable. You planned to take over Nagisa's body to revive yourself. You should be thankful I haven't wiped you away already. And now you still have the luxury to hate me?"
Rozen sneered continuously.
"Fortunately, it's not too late."
These words made the original's pupils contract sharply.
She naturally knew what Rozen meant by "it's not too late."
"You intend to destroy me?"
The original asked coldly.
"Do I have any reason to keep you around?"
Rozen smirked.
With the Beast Vassals contracted to him and the vast mana that surpassed the ley lines now his, Rozen's existence had become irrelevant.
Thus, Rozen naturally wouldn't leave a ticking time bomb within himself. It was only reasonable to eliminate her.
To this, the original roared in fury.
"Even without the Beast Vassals or the mana, I am still the Fourth Primogenitor! I am still an immortal being...!"
That was indeed a fact.
Even though Rozen had taken her Beast Vassals and mana, the original's infinite vitality as a vampire could not be taken away.
If Rozen eliminated the original here, the immortality and regenerative abilities of a Primogenitor would vanish.
That would be a loss.
Without those immortal abilities, Rozen's perfect Mind's Eye would likely have to remain restricted, no longer able to possess the terrifying ability to perceive the records of the world itself, understanding everything, and knowing the past, present, and future.
However...
"This is temporary."
Rozen said calmly.
"My Virtual Aether can enhance the brain. As long as I keep improving, eventually, I'll be able to handle greater burdens. Not to mention, Foreign Mana is elevating me, and one day, my brain will also ascend to a higher dimension."
By then, Rozen would be able to use the full power of the perfect Mind's Eye once again.
As for the original's immortality, it was merely a curse from the gods.
Even if he lost it, no longer possessing the abilities of a vampire, Rozen wouldn't consider it a significant loss.
"Tell me, what reason do I have to keep you?"
Rozen suddenly smiled.
"You...!"
The original gasped in horror.
At that moment, Rozen moved.
"———— Onmyodo's Tsuchimikado solemnly proclaims to Lord Taizan Fukun and the gods of the underworld ————"
"———— On this day, where the sun and moon meets, I, Tsuchimikado Akikan, heir of the Tsuchimikado, shall invoke the secret art ————"
"———— O gods, return the soul to its rightful place ————"
Rozen chanted the incantation for the Taizan Fukun Ritual and clapped his hands together.
Flames immediately ignited on the original's body.
"Ahhhhhh...!"
Amidst a scream, the original was completely consumed by the flames.
Using the secret art of the Taizan Fukun Ritual, Rozen erased the original's soul, ensuring she would no longer exist.
Then, Rozen disappeared from the scene.
Only the vast amount of mana remained, which was fully absorbed by Rozen's magic circuit until not a trace was left.