If Dimitrie Vatler, the lord of the Ardeal principality, truly possesses the strength and uniqueness that Natsuki mentioned, then Rozen understands why Natsuki is so cautious.
Having devoured two third-generation elders, the concentration of his blood can now rival that of second-generation royals, possibly even surpassing them. He can also merge multiple Beast Vassals, a terrifying vampire with a total of nine Beast Vassals. Even though vampires closest to the Primogenitors are hailed as the strongest, it's only natural for him to be considered one.
Ordinary royals typically have around three or four Beast Vassals, while Dimitrie Vatler commands a whopping nine, capable of merging them. Moreover, with his blood concentration possibly surpassing that of royals after consuming two third-generation elders, he surpasses royals in all aspects. How could ordinary royals stand a chance against such a noble?
However, despite being a vampire closest to the Primogenitors, Dimitrie Vatler was defeated by the Nelapsi, and his fate is unknown.
Rozen can conclude that Zaharias must have at least six or seven matrices to achieve this feat.
To defeat a powerful vampire like Dimitrie Vatler, Zaharias must command six or seven Beast Vassals at the level of the Primogenitors. Zaharias probably controls four matrices initially, and with the additional ones obtained from Iblisveil Aziz, he likely possesses enough to defeat Dimitrie Vatler.
Now that Zaharias has reclaimed the matrices from Dimitrie Vatler, how many does he have in total? It's unlikely to be ten, but he may have eight or nine.
Having eight or nine Beast Vassals at the level of the Primogenitors, and among them, those recognized as the strongest of the Primogenitors, Zaharias might hold power even the true Primogenitors cannot contend with.
Even if Rozen has Hokuto, he cannot claim to be able to handle such an opponent.
Of course, Rozen has many aces up his sleeve, like Altera, Kinu, Gyokuto, and various spells and enchantments to boost his magic power significantly.
Over the past decade, his abilities have improved to near their limits in all aspects, making him much stronger than before.
Even without powerful Servants by his side, he now has the capability to venture into Singularities alone. Yet, despite not fearing the Primogenitors, whether he can secure victory is another matter entirely.
According to Rozen's own feelings, without deploying his two trump cards, his current strength is probably comparable to Dimitrie Vatler's level, possessing power closest to the Primogenitors.
If he disregards his energy consumption and fully utilizes Altera, Kinu, and Gyokuto, Rozen can temporarily match or even suppress the Primogenitors. However, it's only temporary; once his magic is depleted, Rozen will be in dire straits.
If he deploys his trump cards, Rozen is confident he can match arms with beings at the level of the Primogenitors. However, these cards aren't easily played: one has a time limit, and the other has a usage limit. If he uses them all without defeating his opponent, Rozen will still be in jeopardy.
Therefore, while Rozen may not fear the Primogenitors, he dare not claim absolute victory.
Natsuki is unaware of all this, ignorant of Rozen's astonishing strength.
However, even so, Natsuki's concern is not unfounded.
Facing the more daunting Zaharias, who recovered even more matrices after defeating Dimitrie Vatler, it's too dangerous for Rozen to recklessly confront him.
In light of this, Natsuki will prevent Rozen from doing so.
"The ritual happening on Itogami Island, you don't need to get involved," Natsuki said firmly. "So, just stay at home obediently and don't go anywhere."
Facing Natsuki's instruction, Rozen unusually retorted, "That won't work, Natsuki-nee. If the arms dealer's goal is to awaken the Fourth Primogenitor, he'll eventually come for Avrora, even if I stay put at home. Sooner or later, I'll have to confront him."
Unless Natsuki intends to abandon Avrora. If that's the case, Rozen won't compromise.
"That's not your concern," Natsuki asserted without hesitation. "I will handle everything."
"But, Natsuki-nee, you yourself said that even you might not be able to defeat Dimitrie Vatler. And since Dimitrie Vatler was defeated by that arms dealer, wouldn't it be equally dangerous for you to confront him?" Rozen furrowed his brow, saying, "Your earlier argument should apply to you as well, right?"
To be honest, even Natsuki probably can't handle Zaharias at the moment. Moreover, as the nation's Attack Mage, she can't currently leverage her authority to mobilize official forces against Zaharias, given that Lion King Agency has recognized the ritual, proving the government's acceptance of its existence. Natsuki, as a government official, naturally can't disobey orders from above and mobilize official forces to confront Zaharias.
Therefore, faced with Zaharias, Natsuki probably has no solution either.
To this, Natsuki said calmly, "You don't need to worry. As long as you stay obediently at home, I can guarantee that neither you nor Avrora will fall into the hands of that arms dealer."
Natsuki's certainty in saying this implies that she indeed has some means. However, these means are not meant to harm others but to protect them. Natsuki is confident that she can prevent others from reaching the objects she wants to protect.
Conversely...
"If you interfere on your own, then I'll be helpless," Natsuki said, raising her eyes. "So, under any circumstances, you're not allowed to get involved in this mess, especially if you still consider me your older sister."
Leaving behind these words, Natsuki turned and vanished into thin air.
Seeing this scene, Rozen was speechless for a while.
"Now what should I do?" Rozen sighed softly.
Clearly, Natsuki has already begun to take a tough stance to protect herself and those around her. Faced with such determination from Natsuki, what should Rozen do?
"I really don't know whether to be happy or frustrated..."