It was a fierce battle, a whirlwind of ice and fire.
Arthur, holding nothing back but his sacred gears, fought Serafall with every ounce of his being.
He knew he had no right to hold back against such a powerful being; doing so would be an act of pure arrogance.
Serafall, however, fought at only half her power, yet it was more than enough to keep Arthur on the defensive.
"You're getting stronger," she said, a hint of admiration in her voice as she effortlessly deflected his attacks.
"As I thought, dragons are unreasonable beings."
She knew from experience that even though devils were considered overpowered, dragons operated on a completely different level of power.
Arthur readily agreed.
"I can't argue with that," he said, the truth of her words resonating deeply.
He knew the difference firsthand, having been human before his transformation.
He had been a normal human without any power, yet now he was able to stand his ground against a powerful being like Serafall, even if she was only using half her strength.
Serafall conjured a barrage of Ice Lances, each one sharp enough to pierce steel.
Arthur countered with his own volley of Crimson Fire Lances, the opposing powers neutralizing each other in a series of explosions that engulfed the entire training ground.
The sheer force would have reduced the area to rubble had Sirzechs not created a powerful barrier to contain the spectacle.
Sirzechs watched, impressed by the sight.
"He's really strong," he muttered, witnessing the clash.
He knew how formidable Serafall was, even at half power.
She was far stronger than a typical high-class devil, yet Arthur was able to hold his own.
A wide smile spread across Serafall's face. She was happy her little sister hadn't chosen an incompetent man.
The one who was going to be with her little sister must be this powerful at the very least; otherwise, she wouldn't have been satisfied.
"Next, I'm going to use my ultimate move,"
Serafall announced, her voice echoing through the explosions.
"It will only be 50 percent of its original power, of course. If you can withstand it, you win."
Arthur nodded, his expression serious.
"Alright. I'll use my ultimate move as well."
Both of them prepared to unleash their most powerful attacks to settle the match.
Serafall began gathering immense amounts of mana, her magical wand glowing with an eerie, icy light.
Arthur, on the other hand, assumed a well-known stance, his body tensing with concentrated power.
From the sidelines, Rias, a massive otaku, felt a thrill of excitement coursing through her.
She knew exactly what he was about to do.
"My Satan!"
Rias gasped, her eyes wide with disbelief.
"Don't tell me he's going to use that!"
Serafall and Arthur locked eyes, the air crackling with anticipation. It was Serafall who made the first move.
"Magical Beam!" she shouted, firing a massive beam of icy energy.
The cold was so intense it made the very air around them freeze.
In response, Arthur's aura intensified, a fiery red glow surrounding him.
He cupped his hands together, drawing in a torrent of dragon mana and even the life-giving energy of the Lifestream.
"Ka... Me... Ha... Me... Haaaa!" he roared, unleashing a powerful blast of crimson fire from his hands.
He finally had a chance to use the iconic Kamehameha.
The two beams of immense power collided, and Sirzechs' eyes widened in alarm.
He had to quickly reinforce the barrier, or the combined force of their ultimate moves would shatter it and destroy everything in the vicinity.
A dust cloud billowed out, obscuring the view of what was happening inside.
As the dust slowly settled, everyone saw that Arthur was still standing, though his body was covered in scrapes and wounds.
Serafall, in contrast, was largely unharmed, save for a small wound and a smudge of dirt on her cheek.
"Wow, a Kamehameha!"
Serafall exclaimed, her eyes sparkling.
As a devotee of magical girls, she also knew about Dragon Ball, at least her world's version.
She smiled happily, a plan already beginning to form in her mind.
'He's a man of culture, too! We can go to events together in the future! Maybe So-tan might even be willing to cosplay with me!'
Arthur used his Lifestream to heal himself.
A golden aura enveloped him, and his injuries were gone in a matter of seconds.
Serafall saw that and immediately came to him.
"That's… What is that power?"
She was curious. Even with her immense power, she couldn't heal up as fast as Arthur.
"Oh, this is my Lifestream."
Arthur extended his Lifestream to her, and Serafall's little injuries were gone.
"This… It is much better than even Phenex Tear!"
Serafall exclaimed in awe.
Phenex Tear was an elixir created by the Phenex clan and was extremely expensive.
To think that Arthur could produce something like that was mind-boggling.
Arthur shook his head.
"Even though it is better than Phenex Tear, I can't store it outside of my body. I can only use it directly."
Serafall felt a pang of sadness when she heard that.
She thought they would have an alternative way of getting healing potions.
Arthur saw her disappointment and couldn't help but say,
"Even though my Lifestream cannot be stored normally, my blood can be used to make potions."
His blood was full of vitality. He was confident that it wouldn't lose out to Phenex Tear.
He could also produce blood endlessly because of his Lifestream.
Serafall thought about it for a little bit before shaking her head.
"Not a good idea. I won't use my and my little sister's fiance's blood."
She made it clear that since Arthur won the fight, it meant he was now her and Sona's fiance.
"Are you really okay with that? I mean, you are a Maou after all."
Arthur didn't mind if she wanted to be his lover, but he wanted to make sure that she really wanted to be with him.
"Of course, I know you are young. When you grow a little more, I might not be strong enough to fight you,"
Serafall said with a hint of melancholy.
She had trained for centuries to be this strong, but Arthur was just a little older than Sona and was already this strong.
She knew that in ten more years, he might surpass her or even Sirzechs.