A few miles away from the Astaroth Estate, Underworld.
"All the important people are truly within the Estate right?"
Standing on top of a branch of blacked tree while overlooking the Astaroth territory ahead of him, Kousuke asked as white haired maid emerged from the casted shadow. It was Grayfia, she was the one who provided the last remaining pieces he needed, and guides him here.
"Yes, though the branch families of Astaroth are scattered around the Underworld, most of them weren't important enough except maybe to fill in the numbers." Grayfia answered curtly.
Obviously he had already informed Sirzechs of his plan ahead of time. Of course the latter tried to stop him at first, but seeing Kousuke wouldn't budge, he sighed before deciding to sides with him. Between Astaroth and Kousuke, it was clear to the Crimson Satan who's more dangerous.
Though the reason Sirzechs relented so quickly was because he had heard rumors that the members of Astaroth Clan were doing some shady stuff while colluding with the Old Satan Faction. He had confirmed it after receiving a report from Grayfia who had been trailing them for a while under his instructions.
Her presence was exposed by third-party mid way just as she senses the Diodora's parents were meeting with someone possessing intense divinity. A powerful lightning attack had scorched her previous spot after retreating almost instinctively. It was Indra, the King of the Gods and Lord of Heaven in Hindu Mythology. Meaning it was an individual on the same level as Zeus from Greek, and Izanagi from Shinto.
Fortunately Indra didn't pursued her after his little warning, of course by then she had already teleport back to the Gremory territory. Whatever they are conspiring behind the scene, Sirzechs didn't like the news one bit. Especially when Indra was involved.
"Is that powerful god residing in that estate as well?"
Grayfia shook her head. Kousuke let out a sigh, fortunately there won't be any distraction. He wasn't afraid of having a face off with the leader of Hinduism, but that might gives the Astaroth family time to escape. That was the last thing he wanted, Kousuke needs them to witness their very downfall in real time and react accordingly to his script.
"Alright, you can leave now. Or I guess watch the show from the distance, just let me know if anyone somehow escapes." Kousuke said nonchalantly before dropping the ground. His aura immediately shifted as if something dwelling deep in his soul is stirring awake from the slumber. Alarm bell started ringing in Grayfia's ears distressingly, it was her instinct screaming at her—to get out of there immediately if she didn't want to meet her maker.
But her legs didn't move, a maid had a duty to fulfill after all. Early on, her husband Sirzechs had instructed her to observe Kousuke closely, especially what kind of power will the latter unleash on Astaroth Estate. Grayfia was curious as well, she had only heard rumors second-handedly. As someone once hailed the title of Silver-Haired Queen of Annihilation, she was just as interested.
When the two guards standing at the entrance of the Estate noticing a human walking towards them, one of them snickered before arrogantly shooing him away with his hand, thinking Kousuke were just lost. It wasn't unusual to came across humans within the Astaroth territory ever since the Heir seems to enjoy toying with them, he'd often be seen inviting unsuspecting individuals to their land. They knew how much Diodora enjoyed tormenting pure nuns, but none dare to let any of that escaped the Astaroth territory.
But Kousuke didn't seems to understand the guard's action as he continue heading towards them. The guard who just shooed him frowned, then he exchanged looks with the other guards next to him before grinning as he slowly unsheathed the sword on his waist. He pointed the sharp blade at Kousuke and warned him again, this time with a provocative smile.
"Don't come any closer, or else!"
Seeing that the human still dares to approach them, the guard was exhilarated. It had been a while since he had fun after being promoted to his current position from guarding the dungeon hundred feet underground. Usually he could beat up people who got into the bad side of Astaroth Clan, as they were locked in said dungeon for the foreseeable torture. With a smile no different than a child opening their christmas present, the guard rushed toward the stupid human and swing his blade effortlessly, aiming to sever his arm instead of going for the kill. Just as the blade was a few inches away from the skin, Kousuke vanished from the spot.
"Huh?"
The guard was stunned, he was certain the human won't have the time to react to his assault. But the next thing he knows, his vision dropped forward before a headless body with blood spurting from the neck entered his sight upside down. 'That's strange, why does that looks like... my body?' That was his final thought before his severed head fell flat to the ground with a thump.
"That's one down, more to go."
"You bastard!"
The other guard seeing his companion being decapitated so quickly that his eyes couldn't follow immediately went full alert. He informed the rest of the guards with a secret technique before throwing himself at Kousuke with his own weapon. Unfortunately, he was also beheaded just as easily in the blink of an eye. They weren't his match at all.
"Two down, and more cockroaches incoming."
Kousuke said calmly. He wasn't in a rush, so he took his time admiring the surrounding as begins walking into the premise. After all, everything will be burn to the ground at the end. He wanted to be very thoroughly with his lesson, so much so that his foreseeable enemies would hesitate before taking action, thus earning him some time to further his plan. It was unfortunate that Astaroth Clan was the unlucky victim that crossed his line. Had it been just normal people doing stupid stuff, he wouldn't necessarily respond back with something this extreme.
Sensing a group of guards approaching his position rapidly, the corner of his lips curled up. Kousuke suddenly raised his hand to the sky and immediately the whole Estate was covered in a mystical barrier. Anyone who tried to escape would ran into invisible walls. They could try throwing demonic magic at it, or even use special artefact to forcefully tear the space open. However, they will soon realize the futility of it, the barrier won't be destroy unless the caster is dead.
"Now then, this is massacre." He muttered apathetically. He was suddenly reminded to the time he had to do something similar to this back in Otherworld. The Demon race, they are known to be very destructive and blessed with human's cunning trait. They are none other than the monster's descendants. A hybrid race that shouldn't existed. Just like their predecessors, they also desires mankind's complete annihilation to welcome the New World. It eventually fall onto his shoulder, the Hero, to made sure that none of that race remained on the face of the Earth.
Yes, the Hero had committed a cold but logical genocide once.