A beautiful day ends with encountering a fiancé.
Hearing the voice from the sky, Rias, who was receiving treatment, paused and looked up.
"Riser?"
As the third son of the Phenex Family, Riser's strength was quite good, ranking high among High-Class Devils.
Coupled with the Phenex Family's exclusive flames, a single enraged strike from him could even injure an Ultimate-Class Devil.
But just as Rias was about to warn Lynn to be careful, she saw Lynn casually wave a hand upward.
Boom—!
Golden lightning erupted, transforming into a crescent-shaped sword aura that engulfed Riser.
When she came to her senses again, she saw a black figure plummeting from mid-air.
With a loud thud, a crater appeared in the ground several meters away.
As the instigator of all this, Lynn acted as if nothing had happened, continuing to treat Rias's injuries.
A green radiance swept across her slender, beautiful leg, bringing a warm, moist sensation along with a tingling numbness.
Although Rias had grown accustomed to this preferential treatment over the past few days and even somewhat enjoyed it.
Having it done in front of an outsider now gave her an inexplicable sense of shame, making her want Lynn to stop temporarily.
But before Rias could speak, a roar sounded first.
"Brat! Let go!"
Golden flames surged.
From within the crater, Riser stood up again, his clothes now tattered and torn.
Possessing the Phenex Family's Immortality, a mere minor injury meant nothing to him.
In the blink of an eye, Riser recovered completely, summoning a ball of flame and hurling it at Lynn.
Seeing this, Rias quickly summoned a Destruction Magic bullet, neutralizing Riser's Phenex flames.
"Rias?!"
Riser's eyes widened in disbelief. "What are you doing!"
"That's what I want to say."
Rias quietly pushed Lynn's hand away. "I don't recall receiving any news about you coming to the human world."
"That's not the point!"
Riser's expression darkened. "As my fiancée, why are you messing around with that kid!"
"Lynn is just helping me treat my injuries."
"Hah?"
"Training isn't child's play. Is it strange for me to have someone help treat my injuries?"
Rias replied without a hint of guilt. "You've trained plenty with your own servants before, haven't you? Wouldn't you help treat their injuries if they got hurt?"
"That's different!"
"How is it different?"
"I..."
Riser was at a loss for words for a moment.
Because of that inexplicable letter, his mood was already not very good.
Coupled with what he had just witnessed, his mind was now filled with the idea of punching Lynn.
Faced with Rias's sophistry at this moment, his mind went blank for a second.
A few seconds later, Riser simply gave up thinking and glared at Lynn with displeasure.
"Kid! What kind of man hides behind Rias!"
"As a Longinus holder! Don't you even have the courage to fight me head-on!"
"You talk pretty funny."
Lynn gave Riser a puzzled look: "You don't actually think you can beat me, do you?"
"Hmph! Why not!"
Riser snorted coldly, the Phenex Family's Immortality flames rising from his body as his aura surged wildly.
"Red Dragon Emperor! In the name of the Phenex Family, I challenge you to a duel here!"
"If you lose! Get away from Rias from now on and don't let me see you again!"
"If I lose instead, then I'll leave Rias! And never appear before you again!"
"What kind of nonsense condition is that."
Lynn raised an eyebrow after hearing this: "You're using Rias herself as a wager—did you ask if she agreed?"
Riser froze: "..."
Only after Lynn's reminder did he realize his words were inappropriate.
Looking toward Rias, sure enough, her expression was unpleasant as she stared at him with clear hostility.
However, with a formidable enemy before him, Riser naturally couldn't lower himself to apologize and chose to ignore it instead.
"Stop spouting useless nonsense!"
"The mighty Red Dragon Emperor—don't tell me you lack the courage to accept a challenge!"
"Such a cheap provocation."
Lynn shook his head slightly: "To be honest, I'm a pretty friendly person by nature and don't enjoy fighting and killing."
"I'll give you one last warning. Leave now, and I can pretend nothing happened."
"Enough talk! I will not back down!"
Riser replied without hesitation.
"Then I'll play along."
Lynn wasn't surprised by this response. He raised a hand to stop Rias, who was about to speak beside him.
"I'll give you a chance. Make your move first."
"Hmph! Arrogant!"
Riser charged straight at him.
Of course, he knew Lynn was strong.
But so what?
He had only been caught off guard earlier by that attack. In an actual fight, it was hard to say.
More importantly, Lynn was just a human.
As everyone knew, humans were fragile, with limited recovery abilities—a little injury could kill them.
But he was different. With the Phenex Family's Immortality, he could outlast his opponent through attrition alone!
Seeing Lynn standing motionless, not even summoning his sacred gear, allowing him to close in.
A cold smile spread across Riser's face as he raised his fist and swung at his opponent.
On the other side, Lynn seemed to respond to his attack by also raising his fist.
Crack!
A clear snapping sound rang out.
The scenario Riser imagined—an evenly matched struggle or falling into a disadvantage—did not occur.
The moment their fists collided, an unimaginable force crashed down.
Not even lasting a second, Riser's right arm snapped and twisted, intense pain flooding his mind.
"What the hell!"
Riser let out a roar.
With ample experience of injury, a mere broken arm wasn't enough to make him lose consciousness.
He immediately abandoned his right arm, pushing forward toward Lynn with all his might as flames churned over his body.
But at the same time, over a dozen arrows burning with black flames appeared between the two.
Sss! Sss! Sss!
With his right arm broken and his posture completely off, Riser had no ability to dodge.
In an instant, the arrows pierced through his body, carrying him backward and smashing him into a crater in the ground.
After that, Lynn's figure flickered and appeared at the edge of the crater, stepping on Riser just as he tried to rise and pressing him back down.
Boom—!
The entire mountain shook violently. The ordinary small crater instantly transformed into a giant pit over ten meters wide, cracks spreading across the ground.
"Haha! Finally got you!"
On the other hand, after being hit with a full combo, Riser wasn't angry. Instead, he curled his lips into a twisted smile.
As a demon who had come of age and participated in over a dozen Rating Games, he still had combat awareness.
After the first exchange, he realized close-quarters combat would be difficult to defeat Lynn.
In that case, he'd trade injury for injury!
Seizing the moment Lynn moved in for the follow-up, he used his remaining left hand to grab the other's ankle.
Violent magical power churned as Riser pushed the Phenex Family's Immortality flames to their limit.
At this distance, his opponent couldn't possibly dodge!
"Die, Red Dragon Emperor!"
Riser roared.
Yet the next second, nothing happened.
The Phenex Family's Immortality flames did not reduce Lynn to ashes. He was still pinned under the other's foot.
"Got any other moves?"
Lynn asked very considerately: "If needed, I can give you another chance to perform."
"Damn it! What the hell is this!" Riser finally noticed the black flames burning on his body.
These were the flames attached to those arrows earlier.
Because Lynn had followed up immediately afterward, Riser hadn't noticed anything wrong at first.
Only now, when summoning the Phenex flames failed, did he realize these flames were still burning on him.
Not only that, but this black fire was suppressing the Phenex flames within him, preventing him from launching an attack.
His Immortality began healing his injuries, after which the black flames rapidly destroyed them again.
Cycling like this, even a Phenex Family member trained in pain tolerance found it hard to endure, his expression twisting.
"It's over, Riser."
Lynn spoke up: "This is Vritra's Curse Dragon Flame. Your immature flames can't handle it. Surrender now, and you can avoid further suffering."
"Don't look down on me! Bastard!"
Riser roared again.
Perhaps anger unlocked his potential—his regeneration speed surged, actually surpassing the Curse Dragon Flame's destructive rate.
His broken right arm fully regenerated. He grabbed Lynn's ankle with both hands, trying to throw him off.
But like an immovable mountain, his efforts didn't shift Lynn's leg even slightly.
"Look down on you?"
Lynn let out a light laugh: "You might have some misunderstanding about me. I'm not looking down on you."
Crack! Crack! Crack!
The cracks on the ground continued to spread as Riser's body gradually sank deeper into the earth.
"Humans don't look down on ants. I never even considered you from the start."
Boom—!
The moment his words fell, Lynn suddenly exerted force. Riser's body pierced straight through the ground.
"Huh?"
In the distant sky, Ravel, who had just finished talking with Sona, widened her eyes in surprise.
On the mountain ahead, a crack ran from top to bottom, splitting it apart, after which the entire mountain began to collapse.
Amid countless boulders, Riser appeared in her sight—body burning with black flames, his aura faint.
Above him, a black-haired boy spread black wings, a spear radiating dazzling light appearing in his hand.
It was a spear made of pure light energy, its surface also burning with the same black flames.
Aiming at Riser, he raised his arm, about to throw it.
Seeing this, Ravel finally snapped back to reality and let out a sharp, piercing scream.
"W-wait! Don't kill him!!!"
...
Immortality ≠ Invincibility.
As a demon of the Phenex Family, Ravel had been taught this on the first day of training.
The so-called Immortality was actually just powerful self-recovery ability.
Using one's will as the foundation and consuming a certain amount of magical power to heal injuries—this was the essence of the Phenex Family's Immortality.
It was just that pure-blooded demons generally had abundant magical power, and the consumption for healing wasn't too high, making it seem like true Immortality.
Similarly, once you understood the principle of Immortality, breaking it was equally simple.
Use an attack beyond limits to erase a Phenex Family member from the molecular level in one strike.
Use superior strength to drain a Phenex's magical power in a prolonged battle or crush their willpower, rendering them unable to fight.
These methods could all break Immortality.
And this was also the reason Ravel felt panicked.
Though she didn't know why, after just a few minutes apart, her brother had been beaten like a dog, completely helpless.
But clearly, he had reached his limit.
Whether in magical power consumption or psychological blows, he had been pushed to the brink.
In this state, taking a targeted hit from a light spear combined with those ominous-looking black flames would guarantee death.
Fortunately, her voice got a response.
"Thank you for your understanding, Lord Lynn."
Looking at the black-haired boy before her, Ravel, now aware of what had happened, spoke up.
"I apologize on behalf of my brother. Please forgive his rude behavior."
"I don't want thanks just in words."
Lynn glanced at Riser, who was still lying there like a corpse.
"Provoking me for no reason, he's lucky he even got to keep his life."
"Do you know about Diodora? Ajuka paid ten Sacred Gears as ransom to get him back."
"Diodora? Ten Sacred Gears?"
Ravel's eyes widened in surprise.
She had naturally heard of Diodora's name.
Among the remaining Devil families in the Underworld, the most prestigious was naturally the Great King Bael family.
Following the Great King Bael family were the Grand Duke Agares family, and the families from which the current Four Great Satans originated.
As the successor of this generation's Astaroth Family, Diodora was quite famous among Devils.
Lynn even fought Diodora?
And even used him as a hostage to take ten Sacred Gears from His Majesty Ajuka?
Faced with this shocking news, Ravel couldn't help but feel skeptical and instinctively looked to the side.
"Miss Rias, is everything Mr. Lynn just said true?"
"More or less," Rias replied.
Things like bloodline orbs were useless to ordinary Devils, but to Lynn, they were treasures.
Furthermore, the Book of Contracts was an extremely powerful summoning-type Sacred Gear, second only to Longinus among Sacred Gears.
Adding these things together, saying ten Sacred Gears was a bit of an exaggeration, but three or four Sacred Gears was about right.
Of course, she was currently speaking on Lynn's behalf, so she naturally wouldn't tell the full truth, and might even help intimidate the other party.
"Ravel, there's something I must tell you."
"Lynn is not only the current Red Dragon Emperor, but also a collaborator with my brother and the others."
"Not long ago, he accepted an invitation to become an Ultimate-Class Devil and will even inherit the name Crocell."
"What this represents, I think you understand."
"...Thank you for the reminder. I will relay these words truthfully to my elder brother, father, and mother."
Ravel fell silent for a moment, then nodded.
To be honest, Rias's words contained a lot of information.
Whether it was collaborating with Satans or being an Ultimate-Class Devil, these were messages that could shock the entire Underworld.
Although she didn't know why she hadn't heard similar news before, Ravel didn't dare take these words as a joke.
Bidding farewell to Rias and Lynn, she picked up the still unconscious Riser and flew off into the distance.
"I'm sorry, Lynn."
Watching Ravel disappear from sight, Rias turned to look at the black-haired youth beside her.
"I didn't expect Riser to suddenly come to Kuoh Town, causing you trouble."
"It's nothing, it's not your fault."
A thoughtful expression appeared on Lynn's face.
In fact, Riser's sudden arrival was also outside his plans.
Although they fought for no apparent reason, the outcome wasn't bad.
Later, he could make some money from that Phenex Family.
Of course, the most important thing was still that letter.
According to Ravel, Riser came to the human world because he received a letter that suddenly appeared.
Clearly, someone was behind this.
"Lynn, do you have any clues?"
Rias, who had also realized this point, asked.
"Some clues, but they need to be investigated."
The ones who instigated Riser to cause him trouble were either high-ranking Devils from the Underworld or Devils from the Old Satan Faction.
The former were ideologically stubborn, disliked the current Four Great Satans from the start, and naturally wanted to test a suddenly appearing Red Dragon Emperor.
The latter had received contact from Diodora, learned of his existence, and needed to test his strength to ensure their subsequent plans.
Of course, the greater possibility was that both were involved.
As could be seen from the original story, those ancient Devils who survived the great war were all fence-sitters.
On the surface, they stood with the current Four Great Satans, but secretly maintained contact with the Old Satan Faction.
It was possible, and highly likely, that both were cooperating to cause him trouble.
"Better leave it to Ajuka."
Lynn took out his communication phone from his pocket.
Whether it was the Underworld's higher-ups or the Old Satan Faction, these were essentially internal conflicts within the Underworld.
Since they involved him, he naturally had to have Ajuka, as a Satan, step in.
Did they really think his knowledge of Another World was so easy to obtain? They couldn't shirk the effort they needed to put in.
...
The Underworld, capital Lilith.
Sirzechs, who was just about to clock out and slack off, hadn't taken a few steps before his friend dragged him back to the office.
"Someone is scheming in the shadows?"
Sirzechs frowned after listening.
He did intend to have Lynn help resolve the engagement on Rias.
But his plan was for Rias to build a good relationship with Lynn, see if Rias was interested in Lynn, and then decide whether to proceed further.
Such a sudden conflict was not within his plans; it even disrupted his arrangements.
Furthermore, there was one more thing that bothered him.
"Ajuka, what is the Old Satan Faction?"
"According to Lynn, it's the largest faction within the Khaos Brigade, composed of the descendants of the original Satans and their followers."
"Khaos Brigade?"
Sirzechs's expression grew even more puzzled.
He had heard of the Khaos Brigade, knew it was a terrorist organization gathering many dangerous individuals.
But that was about it.
As for more detailed intelligence, even Sirzechs hadn't been able to investigate it. Where did Lynn get this information?
Sirzechs asked with his eyes.
Ajuka, receiving his friend's unspoken question, shrugged.
"Don't look at me, I'm not sure either."
"And don't forget, Lynn can even produce knowledge from Another World. He's not as simple as he appears on the surface."
"That's true."
Sirzechs set aside his doubts.
Lynn even had knowledge of Another World, so it wasn't too strange for him to know a bit about the Khaos Brigade.
Rather than investigating the source of Lynn's intelligence, the more pressing issue now was resolving the problem with the Phenex Family.
...