Reincarnated With The Strongest System

William took one more rest day to fully stabilize his soul before instantly teleporting to the Sacred Grove through his weapon, Soleil.

He had left Soleil in his mother's care, which allowed William to instantly travel back to the Elven Capital, after he finished his conquest of Hyperborea.

The moment the Half-Elf appeared inside the Sacred Grove, several explosions were heard in the surroundings, which were signs of fighting.

He immediately went to investigate and found that Charmaine, and the other Valkyries, were fighting against two ladies, in the skies away from the World Tree.

"Oh, welcome back, Will," Arwen, who was watching the battle from afar, said as she hugged her son and kissed his cheek in greeting.

"Mother, what is happening?" William asked. "Who are those two girls?"

Arwen blinked as she looked at her son in surprise. "Superbia and Invidia. You don't know them?"

"Should I know them?"

"Eh? I thought that they were your wives or something, since all the sins were your lovers."

This time, it was William's turn to blink as he looked at his mother with a calm expression on his face.

"This is the first time I'm seeing those two," William explained. "What are they doing here?"

"Um, actually, the two of them are my penpals," Arwen said in an awkward manner. "We've been exchanging letters for the past few years, and I would boast to them about you from time to time. Since both of them were Demons, they couldn't come and visit me here in fear that they would be attacked by the Elves, as well as our guardians.

"However, since I told the Guardians and the King, that two of your acquaintances were coming, they allowed them to pass the borders unchallenged."

William tilted his head to the side as he looked at the two members of the Deadly Sins that were fighting against Charmaine and her comrades. 

"Superbia, and Invidia," William muttered. "The two last remaining members of the Seven Deadly Sins. Mother, can you explain why Charmaine and the others are fighting them?"

"Ah. I didn't know why, but when Charmaine saw them, she yelled that they were part of Felix's group," Arwen answered. "Then her friends joined her in battle, and pushed them away from the World Tree. But, the way I see it, Superbia and Invidia are just dodging and blocking their attacks."

William nodded his head in agreement. The two members of the Deadly Sins were surrounded on all sides, but they weren't counterattacking and merely blocking the attacks.

"Chloee, make them stop," William ordered as he opened a portal beside him.

The beautiful Succubus gazed at the fighters in the sky, and nodded her head with a smile.

A moment later, a loud explosion sounded in the air as the Succubus joined Charmaine and the others in dealing against the two sins, who were now forced to attack in order to defend themselves.

"..." 

"Will, I guess you should go there yourself before someone gets hurt. Although they are Demons, they are still my Penpals, you know?"

William sighed before turning into a lightning bolt to fly in the direction of the battle. As soon as he appeared, Chloee stuck out her tongue and backed away in a hurry.

She had been itching for a fight for a while now, and seeing that something interesting was happening, she wasn't able to stop herself from joining the fray.

"Master, those two are our enemies!" Charmaine shouted as her winged horse hovered beside William. "They were there during the battle in Ahriman's Domain."

"First, calm down," William ordered. "All of you stop fighting."

As soon as William gave out his order, everyone immediately stopped fighting. He then gazed at the two ladies in front of him, who were also looking back at him with an appraising look.

Superbia, who was said to be the strongest of all sins, aside from Wrath, looked at William with a fearless smile.

"Well met, William Von Ainsworth," Superbia said. "Your mother has told us many things about you."

"And she hasn't told me anything about the two of you," William replied. "What are you doing here in the Silvermoon Continent? Did you come here to spy for Felix?"

Invidia, who represented the Sin of Envy, scowled after hearing Felix's name. It was as if the name alone was enough to make her puke, and she hated the fact that she was being grouped with the lecherous bastard.

"I'd greatly appreciate it if you don't lump us with that filthy thing," Invidia stated. "We didn't come here to spy for him, or to spy for the Demon Race in general. We came here to talk to you."

"Talk to me?"

"Duh?"

Superbia rested her hand on her friend's shoulder. She knew that Invidia was starting to vent her frustrations about being attacked by William's forces even though they came peacefully.

"Forgive my friend here," Superbia said. "Our journey has been long and rough. Just as we thought that we were about to get some rest, we were suddenly attacked, and were forced to go on the defense to prevent the situation from escalating."

William nodded in understanding. "For now, let's go to the Sacred Grove to talk. My mother asked me to take both of you there."

Just as William was about to leave, Invidia called out to him in a grumpy voice.

"Aren't you going to make your subordinate apologize?" Invidia asked. "They attacked us even though we meant no harm."

"Apologize?" William asked. "My subordinates don't need to apologize. They are here to protect my Mother and the World Tree from harm. Since they were not aware that you came with peaceful intentions, attacking you was the best course of action. Tell me, if Felix were to approach you and invite you to his bedroom with the excuse of wanting to 'just talk', would you agree to it?"

"No way. I'd fight him to the death before that happens."

"Yeah. My subordinates did just that."

"What kind of logic is that?! This and that are different things!"

William chuckled as he looked at the Sin of Envy who was glaring at him. From her witty comebacks, he assumed that Invidia was someone who liked to quarrel with people.

"Let's go," William said as he ignored the fuming beauty and led his subordinates back to the World Tree.

Superbia whispered something in Invidia's ear, making her friend grumpily follow behind William's entourage.

They had fled from the war in the Central Continent with the excuse that they were going to scout the Silvermoon Continent to see what preparations the Elves were making for the war.

In the past, the two ladies thought that supporting Felix was a good idea. They didn't like the way the Demon Lord Luciel did things in the Demon Realm, so they supported his son so he could usurp his throne.

They didn't expect that the man that they had chosen to support wouldn't live up to their expectations, so they decided to leave. 

The two of them could tell that Felix was looking forward to having his way with them and taking their powers, just like he was doing now with the ladies in the Central Continent.

If not for the fact that Superbia and Invidia had supported him before he became the Dark Heir, he would have already pinned them down and forcefully corrupted their bodies.

To this day, Felix still thought that the two Sins were still enamored with him, so he decided to let them carry out their Scouting Mission, while he enjoyed the beauties of the kingdoms he conquered. That was his greatest mistake, because it allowed Superbia and Invidia to escape, and jump ship to William's side, far away from his grasp.