The next morning.
Ryuichi slowly opened his eyes. He rose from bed and walked to the window, the first rays of dawn spilling over his face. Taking in a long breath, he watched the morning sun climb the horizon.
Truth be told, he hadn't slept a wink that night — he'd spent the entire time training.
After that little bit of "fun" with Rias the night before, Asia had accidentally walked in on them — and the poor girl's jealousy had been written all over her face. The night had ended with the three of them tangled up in quite an emotional mess… though once Rias finally drifted off to sleep, Asia had stayed awake to accompany Ryuichi in his late-night training.
With Asia's Sacred Gear, Twilight Healing — also known as The Smile of the Holy Mother — aiding him, Ryuichi was able to push himself far harder than usual. He amplified the resonance between his magic and her power, enduring the searing pain as his demonic energy roared and boiled within him.
He'd learned something new that night.
Maintaining resonance with a Sacred Gear wasn't enough to keep improving forever. As his own strength and endurance increased, the intensity of that resonance had to rise with it — otherwise, the results would plateau.
If he compared himself to raw black iron, then resonance was the refining process — the hammering heat that turned iron into steel. The stronger he became, the greater the heat and pressure required to temper him further.
And one day, when he could withstand the full burden of that resonance without flinching…
Perhaps that would be the day he could finally wield the Sword and Shield of the Benevolent King at their true, unrestrained potential.
Asia had only managed to stay conscious for about three hours before exhaustion claimed her, but even so, the night's results had been tremendous.
Glancing back at the two girls still asleep in the bed, Ryuichi smiled faintly. Without waking them, he quietly dressed and slipped outside.
He returned a short while later with breakfast in hand — and by then, both Rias and Asia were already awake.
"Good morning," Rias greeted cheerfully, still lounging lazily on the bed. Her voice was soft, her posture elegant — enough to make Ryuichi momentarily recall last night's heat and tenderness.
"Come on, breakfast is ready," he said calmly. "Are you two still coming with me for morning training afterward?"
"Ah, about that," Rias replied, sitting up. "You can skip training today."
"Something's up?"
She and Asia both began dressing, the two girls moving with unhurried grace.
Ryuichi noticed Rias reaching for her black undergarments and walked over to assist without a word. She turned her back to him naturally, and he deftly fastened the clasp for her before glancing at Asia.
"M-me too, please…" Asia stammered, her cheeks tinted pink as she turned around.
A moment later, both girls were properly dressed — Rias now buttoning up her crisp white shirt, her fiery hair slipping free from the collar as she swept it back over her shoulder. She smiled.
"There's a new client request," she explained. "We'll be heading out to investigate right after breakfast."
"Got it," Ryuichi replied with a nod.
In the Devil world, requests were often issued by high-ranking nobles — and Rias, as a pure-blood Gremory, was expected to accept certain tasks from the Dukes. Last time had been a suppression mission against a stray devil; this time, it seemed to be an investigation.
They didn't know the details yet — that would be explained once they reached the site. After breakfast, the group teleported directly to Kuoh Academy's Occult Research Club room to assemble.
Before long, Akeno Himejima and Koneko Toujou arrived as well, and together, the team used a teleportation circle to travel to an ordinary-looking residential area.
A man in a well-tailored black suit stepped forward to greet them. Bowing deeply, he placed a hand to his chest in formal devil etiquette.
"Samuel greets Lady Rias Gremory."
"No need for formalities," Rias said with her usual warmth.
As a high-class Devil, it was natural for lower-ranked devils to show respect before her. Only her peerage — those bound to her through contracts — could speak freely and casually. Everyone else, like this Samuel, had to maintain proper decorum.
"This is Ryuichi," Rias introduced, gesturing toward him, "and this is Asia. My newest servants. I don't think you've met them yet."
Samuel nodded quickly, smiling. "I've heard rumors that Lady Rias had taken on new peerage members. It's an honor to finally meet you both."
"Nice to meet you," Ryuichi and Asia said in unison. Samuel returned the greeting politely.
"Alright," Rias said, folding her arms. "Let's get to the point. What exactly is this secretive mission about?"
Samuel immediately cast a soundproofing spell around them before speaking in a lower voice.
"It's like this… Recently, several of our clan members stationed outside have been attacked by Fallen Angels. We've suffered multiple casualties. Lord Duke suspects the Fallen are up to something again, so he sent scouts to investigate."
He hesitated for a moment, his expression darkening. "But… all contact with those scouts has been lost. They vanished completely. Lord Duke believes they may have been eliminated."
He reached into his pocket and produced a photograph.
Rias and Akeno exchanged a glance. Akeno stepped forward, took the photo, and her eyes narrowed slightly as she examined it.
"This is… the Shin'un Building," she said. "About three kilometers west of Kuoh Academy."
She recognized the place immediately — the tall office complex that could be seen from the school courtyard.
"Heh," Rias said with a small smile. "So it's right in my jurisdiction."
"Exactly," Samuel replied. "That's why the Duke thought of you. He's asking that you take on the request — investigate the building with your peerage and determine the Fallen Angels' purpose."
"Understood. I'll take the commission."
It was an easy decision. Anything that happened within Kuoh's territory was her responsibility as its ruling Devil.
Once the briefing ended, Rias turned to her servants.
"Has anyone noticed anything unusual about that building lately?"
"Not really," Akeno said with her usual serene smile. "But Fallen Angels have always been… restless creatures, haven't they?"
"They're annoying," Koneko muttered simply, her dislike of them plain as ever.
Ryuichi, however, stayed quiet, his gaze shifting briefly toward Asia.
"What about you, Ryuichi?" Rias asked, noticing his silence. "Anything come to mind?"
"…Actually, yes." He nodded thoughtfully.
He recalled the battle during Asia's rescue — the Fallen Angels had mentioned being involved in something big. And that Asia's Sacred Gear played a key role in it.
And now, this new incident — their scouts disappearing, the same enemy involved…
Could all of this be connected?
When he finished explaining his thoughts, the others fell silent for a moment.
"…You might be right," Rias said at last, her tone serious. "If that's the case, then this investigation just became far more important."
She smiled faintly, crimson hair catching the light. "Looks like we'll be giving that place a very thorough inspection."