The Living World, outskirts of Kuoh Town.
Since it was the weekend, Rias and the others did not have classes for these two days.
When Lynn arrived, Kiba and Koneko had already started today's training.
"Lynn, you're here."
Rias nodded slightly and greeted him.
After exchanging greetings, Rias took out ten blood-colored orbs and a book and handed them to Lynn.
"These were sent by His Majesty Ajuka. He asked me to pass them to you."
"Not bad, the efficiency is quite high."
A smile appeared on Lynn's face.
The day before yesterday, after capturing Diodora, he exchanged the ransom with Ajuka in return for releasing him.
The bloodline orb was still from the Crocell Family.
Lynn wanted to try if repeatedly consuming the Crocell Family's bloodline orb could enhance the effect of his Monstrous Strength talent.
As for the artifact shaped like a book...
"This is the Book of Contracts."
Rias introduced, "As long as the other party voluntarily signs their name in the book, a contract can be established with the user, allowing for spatial teleportation."
"Normally, it's used for contracting familiars, but it can also be used to contract humans, though there are some limitations in usage; there are ten contract slots."
"Oh right, His Majesty Ajuka asked me to pass on a message. He said spatial-type divine artifacts are hard to find, and this one already has the closest effect. If you're not satisfied, you can wait a few more days."
"No need, this one is quite good."
Lynn took the Book of Contracts back.
The spatial divine artifact he originally wanted was one that could record coordinates for long-distance teleportation.
But if that wasn't available, the Book of Contracts was still a good choice, usable for those around him.
With a thought, he summoned the boosted gear, and the Mist engulfed the bloodline orb and the divine artifact.
A few seconds later, the Devil Bloodline within Lynn grew stronger again by several points, and the Monstrous Strength talent was reinforced as he expected, upgrading from doubling his strength to increasing it by two and a half times.
The increase wasn't huge.
But considering his own strength was already high, this amplification was acceptable.
On the other side, Ddraig, who was wandering outside, returned his consciousness to his main body upon hearing Lynn's call.
Soon, the ability of the Book of Contracts was completely solidified.
"Partner, I feel like I can only solidify 1-2 more divine artifact abilities before reaching my limit."
"I know, you can go now."
Lynn responded mentally, and with a thought, he kicked Ddraig's consciousness out of the divine artifact.
This was a new method he had mastered a few days ago.
As long as the Mist clone outside wasn't destroyed, he could send Ddraig's consciousness over at any time.
With this new ability, Lynn no longer needed to send Ddraig out every night to stretch his legs.
Because he had given him a year's worth of magic power, Ddraig had already gone traveling nationwide.
"Lynn, how was it?"
On the other side, Rias approached as the Mist disappeared and asked, "Was the divine artifact ability solidification successful?"
"It was successful."
Lynn raised his hand and summoned a book, "Are you interested in testing the artifact's effects with me?"
"Of course."
Rias nodded.
For a devil, signing a contract was a common thing, it was just that this method of signing was a bit special.
Rias wrote her name in the Book of Contracts and quickly felt a connection form between her and Lynn.
Buzz~!
A faint spatial fluctuation arose, and Lynn's figure appeared next to Rias without any warning.
"Is this the ability of the Book of Contracts?"
Akeno saw this scene and a playful smile appeared on her face, "Rias, you'll have to be careful when changing clothes in the future, Lynn might teleport over at any moment."
"Don't worry, I won't let anything like that happen."
Rias replied.
This teleportation ability was indeed quite subtle.
As the contracted party, Lynn could unconditionally teleport next to her.
If she wasn't careful, the subtle situation Akeno mentioned could indeed occur.
But the solution was equally simple.
She just needed to wait until the test with Lynn was over and ask Lynn to erase her name from the book...
Boom—!
"Huh?"
Rias stared at the ground suddenly cracking beneath her feet and the powerful energy surging within her body, looking stunned.
Then, as if she had discovered something, she abruptly turned her head to look at the black-haired youth standing beside her.
"Lynn, what did you do?"
"I'm testing the ability of the Book of Contracts," Lynn replied as a matter of course.
Although it wasn't a Longinus, the quality of the Book of Contracts was absolutely top-tier among ordinary divine artifacts.
Teleporting oneself next to the contractor, or teleporting the contractor next to oneself, was only one of its effects.
In addition, the Book of Contracts also possessed the effect of transferring magic power and strengthening the contracted party.
"Rias, do you feel any discomfort in your body?"
"No."
"Then I'll continue."
Lynn transmitted more magic power over.
Visibly, Rias's aura began to soar straight up, even shaking the entire mountain range.
Kiba and Koneko, who were training outside, felt this aura and rushed over immediately to check the situation.
Looking at Rias, whose red hair was fluttering and whose aura was almost materialized, they both showed expressions of surprise.
"Buchou, are you alright?"
"I'm fine, I'm accompanying Lynn to test his new ability."
Rias raised her palm, and Destruction Magic continuously gathered, instantly forming a giant magic missile dozens of meters wide.
"This only consumed one-twentieth of my magic power?"
This giant Destruction Magic Missile was Rias's most powerful move.
Under normal circumstances, summoning two giant Destruction Magic Missiles was her limit, but now her magic power had increased tenfold, making it possible to fire twenty without issue.
Furthermore, besides the change in magic power, she could feel her physical fitness had also improved.
She had now completely surpassed the realm of a High-Class Devil, her strength comparable to an Ultimate-Class Devil.
"Lynn, you didn't use all your magic power to strengthen me, did you?"
"You're overthinking it, less than one-tenth was used."
"Huh? Really?"
"I have no reason to lie to you about something like this."
Lynn raised his hand and gestured towards the boosted gear, "Don't forget, I can multiply myself."
Just like how crimson light arrow could link with Dragon Flame, after being engulfed, the ability of the Book of Contracts combined with the transfer ability of the boosted gear.
The simple transfer of magic power turned into a direct transfer of strength and could form a secondary link with the multiplication.
One-tenth was the result of Lynn's initial multiplication.
If he multiplied enough times, perhaps even less than one percent of his power would be needed to strengthen Rias to the level of an Ultimate-Class Devil.
"This is an unexpected bonus."
Lynn sized up Rias, "How does it feel after being strengthened? Is there any tendency for the power to go out of control?"
"No, I just need to adapt to it."
"Then today, fight me in this state. That way, you won't run out of magic power after only a few minutes of fighting."
Rias's goal was to develop her Destruction Magic.
Having more magic power available was naturally a good thing for her, and Rias nodded in acceptance.
As for the previous thought of canceling the contract after testing the divine artifact's effect with Lynn, she had already cast it aside.
The risk of having her changing room seen was nothing compared to the importance of power! Having inexhaustible magic power really felt amazing!
Seeing Lynn ready, she raised her hand and launched hundreds of magic missiles, beginning today's training.
...
Time passed, and three days flew by.
At the same time Rias was gaining strength and engaging in fierce battles with Lynn.
In the Underworld, at the Phenex Family's residence.
Riser, who was enjoying intimate time with his retainers, received an unsigned letter.
"This is... what kind of joke is this!"
"What's wrong?"
Not far away, Ravel, who was reading a fashion magazine, lifted her head with a look of confusion on her face.
It was the first time she had seen such an expression on her brother's face; it was as if he had been cheated on.
Out of curiosity, Ravel leaned over and glanced at the letter in Riser's hand.
[Rias Gremory is involved with the inheritor of the Ancient Martial Arts Family, Lynn, attempting to break off the engagement through this means.]
Uh, he really was cheated on.
Ravel's expression became subtle.
She shifted her gaze from the letter and looked towards the mature woman standing to the side.
Yubelluna, where did this letter come from?"
"It just appeared in my room a moment ago."
"Just appeared?"
Ravel frowned.
Yubelluna was Riser's Queen; it was impossible for her to lie about something like this.
Since she said it appeared suddenly, it meant the person who delivered this letter didn't want their identity exposed.
"Lord Riser, please calm down."
"This letter is suspicious. The person who sent it wants to anger you and sow discord between you and Lady Rias."
What Ravel could think of, Yubelluna naturally could too, and she immediately spoke up to remind him.
However, these words did not calm Riser down; his expression remained dark and unsettled.
The letter was suspicious.
Of course, he knew that.
But the contents of this letter were something he simply couldn't ignore.
Rias was his fiancée.
Regardless of any other considerations, Riser had to verify the truth of this matter.
"Yubelluna, prepare a teleportation circle for me. I'm going to Kuoh Town to see Rias."
"Understood." Yubelluna also knew the importance of this matter and immediately turned to leave the room.
"Brother, I'm coming too." Ravel spoke up; she was also curious about this incident.
Riser did not refuse.
Ravel was his sister and also a member of the Phenex Family; there was no saying about family scandals not being aired in public.
After Yubelluna prepared the teleportation circle, Riser took Ravel with him and teleported to the Occult Research Club.
As Rias's fiancé, Riser had been here a few times before.
However, when he and Ravel teleported to the Occult Research Club, they unexpectedly found no one inside.
"There seems to be someone in the classroom on the first floor."
Ravel looked down and reminded him.
"That person is Rias's Bishop, but he's under a ban from His Majesty the Satan and can't move freely."
Riser replied. He was familiar with Rias's servants, especially the time-type user, Gaspar.
Knowing he wouldn't get any information from him, Riser went straight to the student council to find Sona.
"Now this is a rare guest."
Sona adjusted her glasses. "Long time no see, Mr. Riser. Are you here to ask me about Rias?"
"That's right. Do you know where she is?"
"I do. She's been undergoing special training recently. At this time, she should be in the mountain range to the west."
"Special training?"
Riser's expression relaxed slightly.
When he didn't find Rias in the club earlier, he had thought she might have gone on a date with that man named Lynn.
It seemed now he had been too hasty.
Right, he knew Rias's personality well. Why would she inexplicably get involved with some random man?
"Miss Sona, do you know Lynn?"
At that moment, Ravel's voice rang out.
"I do. He's a transfer student from the Dragon Country and is currently accompanying Rias in her special training."
"Special training? Is he very strong?"
"Mm, very strong."
Sona glanced at Riser.
As soon as she mentioned Lynn accompanying Rias's training, the other's expression turned ugly again.
As an intelligent person, Sona vaguely sensed something. After a moment's thought, she tactfully reminded them.
"Lynn is the wielder of the legendary Longinus, the boosted gear. His strength is on a monstrous level, completely different from ordinary people's."
"I see."
Ravel nodded thoughtfully.
Although the identity of a Longinus wielder was somewhat astonishing.
Recalling the information in that letter, everything became reasonable again.
The legendary Red Dragon Emperor—that man named Lynn indeed had the qualifications to help Rias break off the engagement.
"Brother, what do you think?"
"..."
"Huh?"
Ravel was taken aback. She turned her head to look beside her and only then noticed that Riser had disappeared at some point.
"He's already left."
Sona pointed to the open window nearby.
"What the... that idiot brother of mine."
Ravel sighed, holding her head.
Leaving in such a hurry, his intentions were obvious.
However, Ravel wasn't in a hurry to chase after Riser; she had confidence in her brother's strength.
"Miss Sona, could you tell me more about that Red Dragon Emperor? I'm somewhat interested in him."
"Of course."
Sona nodded calmly.
She also didn't go after Riser.
As one of Rias's close friends, she had some understanding of Lynn's power.
Rather than worrying about whether Lynn would get hurt, she was now more curious about how Ravel knew the name 'Lynn'.
Looking at the Blonde Girl before her, Sona subtly began fishing for information.
...
Meanwhile.
After leaving the student council, Riser immediately went all out, heading towards the west of Kuoh Town.
Although both were High-Class Devils, Riser had the advantage of age and had cultivated for a longer time.
Traveling at full speed, it only took him a few minutes to find the place Sona had mentioned.
It was a mountain range enveloped by a large Barrier.
Descending from the sky, Riser easily entered the Barrier and sensed Rias's presence.
"Over there?"
Riser took a deep breath and looked towards the mountaintop.
After all, as the heir of the Phenex Family, Riser knew he couldn't be too impulsive.
The other party was, after all, a Longinus wielder.
Before figuring out the truth, he needed to stay rat...
"Rational my ass!"
Looking at that black-haired youth holding his fiancée and even feeling her up.
Riser felt a weight press down on his head. The last shreds of reason in his mind instantly transformed into killing intent.
"You bastard! I'm going to chop your hands off!"
...