"Mmnn... chupa, slurp, slrppp, nfu..."
"Kuh... Ahh, Rias!"
"Nfu... suck, haufff?"
"Ahh... That feels amazing."
On the bed in Kazuki's room, Rias, now completely naked, was fervently sucking on Kazuki Fuwa's throbbing cock.
His member was so large that she couldn't take it all the way to the base, but even so, her saliva coated the head and about half of his shaft.
"But Rias, why so suddenly...?"
"Mnn... Because I wanted to do this for you... Did you not like it?"
When she asked this, Kazuki gently stroked her head and replied.
"Of course I liked it!! But I was just surprised, that's all."
Honestly, Kazuki could be so dense at times. Here Rias was, completely turned on by his words, ready to offer herself entirely to him, and yet he seemed oblivious.
"...I'm your woman, Kazuki!! It's only natural that I want to serve you."
When she said this, Kazuki finally seemed to understand, letting out a wry smile.
"Rias... You don't have to push yourself, you know?"
"I'm not pushing myself! Honestly! It's not just about the promise—I want you to take me right now! Can't you see how much I'm burning for you!?"
With that, she took Kazuki's right hand and guided it to her dripping wet pussy. As his fingers touched her, a lewd, wet sound echoed through the room.
"Rias... You're this wet already!?"
Kazuki sounded surprised but began to move his fingers skillfully.
"Nnaah! Kazuki, right there, yes!"
As Kazuki's fingers moved, her entrance opened wide, and a flood of sweet nectar gushed out. Her clit stood erect, eagerly awaiting his touch.
"Fuu, hmmm!... Nn, ahh, Kazuki, Kazuki!"
Kazuki's fingers plunged deep into her pussy. Normally, he would move gently, taking care not to overwhelm her, but now, perhaps driven by his own arousal, he inserted two fingers deep inside and moved them vigorously.
"Hmm... Ahh, Kazuki... I-I'm cumming, nnaahh!!"
In an instant, Rias reached her climax. Breathing heavily, she gazed at Kazuki with lust-filled eyes.
"Kazuki... Isn't it okay now? I can't hold back anymore. So, can you please put it in?"
She climbed on top of him, aligning her hips with his. 'If I lowered my but now…'
Just the thought of it made her heart race wildly. Her excitement and nervousness caused her juices to drip onto the tip of Kazuki's cock, forming a transparent bridge between them. As she gulped and prepared to lower herself,
"Not yet, Rias."
Kazuki gently pushed her body back, causing her to land on his thighs.
"...Kazuki?"
'I have been rejected?' For a moment, despair flashed through Rias's chest. But then,
"Sorry, Rias... I want it too. I want to thrust my dick inside you, fill you with my cum, and make you mine in every way! But not yet. We can't do it yet!!"
Kazuki placed his hands on her shoulders and spoke firmly.
"...Why? Even my brother has given his approval. Father will surely agree too. It's just a matter of time, isn't it?"
"…No. It's still not allowed."
"Why!?"
"Because that was our promise!"
"!?"
The sharpness in Kazuki's tone forced Rias to bite back her words. His gaze burned with resolve, though his fingers trembled faintly against her skin.
"…Rias. We're being tested!! Whether you're worthy to be the next head of the Gremory clan… and whether I'm worthy to stand as your husband. You understand that, don't you?"
Rias nodded reluctantly, her crimson nails digging into her palms.
"If we… indulged now, there might be no severe punishment. But Lord Gremory would never trust me again. I'd be seen as a man who breaks his vows. So… not yet. I'm grateful—thrilled—that you desire me this way. But I swear, I'll earn undeniable glory soon. Until then… Rias, can you endure this hunger a little longer?"
Her breath hitched. Without a word, she pressed her forehead against his shoulder, her voice trembling.
"I'm a pathetic master, aren't I?"
"Rias…"
"Succumbing to lust and trying to break our promise… I'm truly unfit to lead."
'He's restraining himself too, and yet here I am, trying to seduce him like some desperate fool!' The shame burned hotter than her arousal. Her brother's earlier words had cut deeper than she'd admitted.
Her mind flashed back to the aftermath of Kazuki's brutal clash with Sirzechs…
"Hahaha! Well, well~ I give up, I give up! You win, Kazuki-kun. Seriously, you're something else."
"Ah, thank you," Kazuki replied, looking somewhat bewildered by the excessive praise from Rias's elder brother.
"However, to think you could destroy my barrier... That's some terrifying, destructive power," Sirzechs continued, his tone shifting to one of awe.
Standing nearby, Grayfia wore an expression that was hard to read—somewhere between exasperation and admiration.
"Brother! You owe us an explanation, don't you?!" Rias, on the other hand, was visibly furious.
She couldn't believe her brother had acted without informing her and had even gone as far as to harm Kazuki. No matter how much she respected him, this was unforgivable.
"Alright, alright. I'll explain, so calm down a little... Now, you must realize that Kazuki-kun's existence is beyond the norm, right? In terms of combat power alone, he's already on par with a high-class devil. No, with that Gigantic form of his, he might even rival a supreme-class devil. To think such a being is your servant... It's baffling how he only required one piece to reincarnate."
That was something Rias had also been pondering. Issei had been reincarnated using seven pawn pieces. At the time, they hadn't known Issei was the Red Dragon Emperor, so the number of pieces required had been surprising, but now it made sense.
However, what about Kazuki? Wasn't it strange that Kazuki, who harbored the power of the Guyver, had been reincarnated using only one evil piece?
There was no clear answer to this. 'Perhaps we could find out by asking Ajuka Beelzebub, one of the Four Great Devil Lords and the creator of the 'Devil's Piece'!'
"His power has already surpassed yours. Do you understand what that means?"
"Ugh... Yes," Rias reluctantly nodded.
"When a servant surpasses the power of their 'King,' who is a high-class devil, misfortune often follows," Grayfia explained, sensing that Kazuki didn't fully grasp the situation.
"Misfortune?" Kazuki asked, his confusion evident.
"Yes. For better or worse, devils live by the creed of strength. In fact, after the Great War, the four young devils who succeeded the previous Satans were the strongest of their time. And when a servant becomes stronger than their King, they may start to look down on their master, or worse, become intoxicated by their power and turn against them, becoming 'rogue devils.'"
A servant that the Master cannot control is extremely dangerous. In other words, this whole incident was a test—to gauge just how powerful Kazuki, the Guyver, truly was, and to see if he would betray his master, Rias Gremory.
"So? Did I pass the test?"
"Of course! As a Devil Lord, I acknowledge you. However, the problem lies with Rias."
"!!"
At her brother's words, Rias flinched visibly.
"Rias. Your peerage is steadily coming together. However, with members like Issei Hyoudou, the Red Dragon Emperor, Xenovia, the wielder of the holy sword Durandal, and Yumi, who has achieved the 'Forbidden Balance Breaker,' it is expected that in the near future, they may surpass you in strength. Will you be able to keep them in line?"
"Th-that's..."
"Unfortunately, young lady, you haven't shown much growth since entering high school. As things stand, there's a possibility you may not be able to control them."
"Grayfia!?"
"Hmm... I also met them yesterday, and I'd like to believe there are no members in your peerage who would become strays. However, we must always prepare for the worst. Especially with Issei, you need to be careful, Rias."
"Issei? There's no way he would become intoxicated with power—"
"It's said that every previous Red Dragon Emperor lost control of their power and met an early demise. Can anyone truly say he won't follow the same path?"
"..."
"To prevent that, a 'King' must demonstrate their worth to their servants. Whether it be through strength, intellect, or charisma, it varies from king to king. You should think carefully about what kind of king you aim to be."
"...Yes."
The weight of her brother and Grayfia's words pressed heavily on Rias, leaving her utterly dejected.
"That being said, Kazuki. I apologize for tonight. Let me quickly prepare a Phoenix Tears—"
"No, that won't be necessary."
Kazuki said this as he released his [Gigantic Armor]. The Gigantic Armor instantly reverted to a cocoon-like state and disappeared somewhere. And Kazuki's arms were fully restored.
"This is...!"
"They're completely healed..."
Kazuki, having released his armor, explained.
"To put it simply, the Guyver can regenerate lost limbs. Although I can't release the armor until the regeneration is complete."
'If you had such an ability, you should have told me earlier! You nearly gave me a heart attack.' Rias thought.
"Armor...? Is that what you call transforming into Guyver?" The devil king asked with keen interest.
"Yes. By 'arming' myself and donning the 'Guyver Armor,' I become [Guyver]."
"I see. So, it's [Guyver: The Bio-boosted Armor], huh? I like it!"
Sirzechs seemed oddly excited. On the other hand, Kazuki looked inexplicably surprised, while Grayfia rubbed her forehead in exasperation.
"Then, I'll take my leave for tonight. Let's go, Rias."
Kazuki excused himself to her brother and urged the despondent Rias to follow.
"Kazuki... Okay."
He took Rias' hand and began to walk.
"Ah, Kazuki. Do you know what 'Guyver' means?"
At Sirzechs's question, Kazuki stopped in his tracks.
"...I'm not sure what language it's from, but when I first armed myself as Guyver, a phrase came to mind. It seems to mean... 'Outlier.'"
"'Outlier,' huh? That's a good way to put it."
Without responding further, Kazuki lifted Rias into his arms, spread his wings, and flew off into the night…
As soon as they returned to the room, Rias pushed Kazuki down onto the bed.
Which brings us to the present…
Suddenly, Rias murmured softly.
"My Onii-sama is right! Kazuki, of course, but even Yumi and Issei are growing stronger by the day. Compared to them, I..."
It seemed the Devil Lord's scolding had struck a nerve. Rias was more downcast than usual. She was surprisingly fragile when it came to setbacks. Born with exceptional talent, she had never truly faced failure until now.
Whether it was during the game against Riser or when Yumi mentioned leaving her peerage, Rias tended to crumble when faced with obstacles.
'I can't leave things like this, but I'm not good at talking, so I wonder if I can encourage Rias?' He wasn't sure, but he decided to speak his mind.
"Hey, Rias. Have you ever done anything special to get stronger until now?"
"Special? Hmm... I learned how to handle magic from my mother and Grayfia, but I don't think I've done anything particularly special. Why do you ask?"
In other words, she had relied solely on her innate talent to get this far. In a way, that was impressive.
"Then you'll be fine. You can get even stronger, Rias."
When Kazuki stated this firmly, Rias widened her eyes and asked.
"How can you be so sure?"
"Do you think I'm strong?"
Kazuki turned the question back on her.
"Of course. Your mastery of the Fuwa Enmei-ryu martial arts, combined with the power of the Guyver... Even wounding my brother like that is something only a handful in the underworld could do."
"Thanks. Then do you think I got that power easily?"
"Well..."
'Good.' If she had said "yes," Kazuki wouldn't have known what to do.
"I don't like remembering it much, but my grandfather's training was brutal. For example—"
Kazuki recounted some of the harsh training sessions his grandfather had put him through for the Fuwa Enmei-ryu. The details were too gruesome to share in full, but as he spoke, Rias' face grew increasingly pale.
"Th-that's... That's some intense training."
"Yeah. It was hell..."
Just recalling it made Kazuki feel sick. He was reminded once again just how insane his grandfather was.
"Well, I'm not saying you have to go that far, but why not start with some training? If you want to change, you have to take the first step. Nothing will change if you don't move."
Rias pondered his words carefully, taking a moment to think.
"Yeah... You're right, Kazuki. Nothing will change if I don't take action... Okay! Kazuki, I'll show you I can change. So, watch me, okay?"
The weakness in her eyes from earlier was gone. Instead, they shone with the same bold, vibrant light that had drawn Kazuki to her in the first place.
"Yeah, I'll be watching."
Their faces naturally drew closer, and soon their lips met in a deep, passionate kiss.