In DxD Starting with Sign-Ing in as the Red Dragon

(Note: The story will primarily focus on the DxD world, with occasional trips to the Campione! world to fight monsters. To prevent readers who skipped the Fate arc from being confused about certain items and the protagonist's current status, a brief summary of the Fate arc will be provided. Readers familiar with the Fate arc can skip this summary or use it to refresh their memory.)

Summary of the Fate Arc:

Characters Recruited:

Most of the Fate world's characters have been recruited. Those with less screen time, such as Ayako Mitsuzuri, Taiga Fujimura, Bazett, Claudia, and Caren, will be mentioned briefly. Since this is a fragmented version of the Type-Moon universe, not all characters from other Type-Moon works can be recruited at once.

Power Level:

The protagonist, Akira, has advanced from a high-class demon to a mid-tier Demon King (capable of fighting 233 opponents at once).

Agumon has fully stabilized his foundation, reaching the peak of the Super Demon King level. He has also gained a human form—a golden-haired, golden-eyed girl with a Holy Cross engraved in her eyes. She has named herself "Holy Response."

Key Rewards from the Fate Arc:

Second Awakening of High-Dimensional Succubus Bloodline: Grants the ability to charm the world, creating a "Child of the World" effect that ensures events favor the protagonist. In combat, this provides near-infinite energy and powerful buffs.

Star Sea Dragon King's Soul: Possesses the power of the "Virtual Star: Tai Sui," capable of sealing entire world clusters. The more worlds sealed, the stronger the soul becomes.

Second-Generation Breakthrough Pieces: Advanced demonic pieces that automatically split based on the races of Akira's servants. These pieces are undetectable and generate one "Pawn" piece per day for each race, theoretically giving Akira an infinite supply. They also enhance resurrection abilities, allowing Akira to revive others as long as fragments of their body and soul remain.

Blessed Holy Cross: A cross that can store Akira's power, albeit at two levels lower than his full strength. It can be used to intercept heroines during time travel and alter fate.

Fate Shifter: A device that absorbs a person's fate energy and allows travel to key points in their past. Absorbing male fate energy requires their full power, while absorbing female fate energy requires the use of the High-Dimensional Succubus Bloodline.

Sword of Salvation: A divine sword that allows Akira to form contracts with gods on his own terms. Unlike Rama's version, Akira's sword is not bound by divine contracts, though it remains a blank slate for now.

Partial Gate of Babylon: A portion of Gilgamesh's treasury, converted into divine weapons that grow stronger with Akira's power.

Agumon's Foundation Repair: Using the Holy Grail and the Root of the World, Akira fully repaired Agumon's foundation and unlocked his human form.

Twelve-Winged Fallen Angel Form: A form with peak Super Demon King power, capable of fighting at full strength for 10 minutes after a 24-hour charge. This form has infiltrated the Fallen Angels through Lavinia's connections and Agumon's research, positioning Akira as a potential future leader of the Fallen Angels.

Developments in the DxD World During the Fate Arc:

After the Kokabiel incident, Illya and Xenovia remained in Kuoh Town.

The Fallen Angels, Azazel and Baraqiel, arrived in Kuoh Town to prepare for a three-way faction meeting.

The Holy Grail War's events triggered a self-destruction program in the world's consciousness.

Jeanne d'Arc's spirit, after her spiritual core was destroyed, escaped to the DxD world and merged with a descendant of Jeanne, lying dormant until Akira can restore her.

Jeanne's power has grown to the peak of the Demon King level, and with Akira's advanced pieces, she has become a Super Demon King, rivaling Cao Cao in strength.

Saber, Medusa, and Medea will play significant roles in leading the Hero Faction and the Greek pantheon in future arcs.

Kuoh Town, Student Council Room

Knock, knock, knock~

The sound of knocking interrupted the two bespectacled girls working in the student council room.

Sona Sitri and Seekvaira Agares looked up simultaneously and replied, "Come in."

The door opened, and a stunning red-haired beauty strode in. Her crimson hair cascaded down her back, and her tall, curvaceous figure was complemented by mesmerizing blue eyes. In terms of looks, status, and aura, she was undoubtedly a top-tier beauty.

However, upon entering, Rias Gremory noticed something that left her feeling a bit disheartened.

"Sona, have you been using some high-end skincare products lately? You're glowing more than usual," Rias remarked.

Rias had always believed she outshone Sona in both looks and figure. But today, she couldn't help but feel a pang of inferiority. It was baffling.

Sona set down her documents and smiled gently.

"Oh, that? It's probably because I recently advanced to the Ultimate-Class Devil level and awakened the Sitri clan's innate abilities," Sona replied, not mentioning that her newfound radiance was also due to her relationship with Akira.

Rias's excitement about her own advancement to the Ultimate-Class Devil level waned slightly. She had hoped to show off to Sona, but it seemed Sona had already surpassed her.

"I see…" Rias said, feeling a bit deflated.

Rias also noticed that Seekvaira seemed more radiant than before, though she didn't feel close enough to ask about it.

"Since you've also advanced, maybe we can spar sometime to test our new strength," Rias suggested.

"No need, Rias. I've already adjusted to my new power," Sona replied calmly.

Sona hadn't told Rias the full truth—she had already reached the Demon King level, thanks to Akira's influence and the second-generation Breakthrough Pieces. Seekvaira, on the other hand, was at the peak of the Demon King level, just one step away from becoming a Super Demon King.

"Alright, if you don't want to, that's fine," Rias sighed, turning her attention to Seekvaira.

"Lady Agares, I actually came here specifically to see you," Rias said.

Seekvaira set down her work, removed her glasses, and smiled warmly.

"Please, call me Seekvaira. I'd prefer if we could be friends rather than maintaining a formal relationship."

Rias was taken aback but quickly extended her hand.

"Likewise, Seekvaira. I'd be happy to be friends."

After shaking hands, the two sat down.

"So, Rias, what brings you here?" Seekvaira asked, sipping her tea.

"It's nothing major. I was hoping to use the Agares family's platform for some transactions," Rias replied with a soft smile.

A few days ago, Seekvaira had returned to the Underworld and revealed her Demon King-level strength, shocking everyone. At less than 20 years old, she was a peak Demon King, a feat unheard of in the demon world. This had led to her becoming the acting head of the Agares family, with her formal ascension to the position imminent.

"You're looking for spirit medicine to stabilize your power, right?" Seekvaira guessed.

"Not just that. I'd also like to see if there are any powerful Sacred Gears that suit me," Rias added.

Seekvaira raised an eyebrow.

"Sacred Gears? Are you serious?"

"Of course," Rias nodded.

"Aren't you worried about what the noble families in the Underworld will think? Using a Sacred Gear is seen as beneath a noble's status."

"I don't care about their opinions," Rias said firmly.

"They're just old demons clinging to outdated traditions. They reject the current Demon Kings and powerful reincarnated devils. The only way to shut them up is to show them real power."

Seekvaira smiled, clearly pleased with Rias's response.

"In that case, would you like to join us in opposing the old system of the Underworld?"

Rias was taken aback. She had come to buy spirit medicine, but now the conversation had taken a political turn. Still, the topic intrigued her.

Meanwhile, a teleportation circle lit up in the student council room. A tall, black-haired beauty with glasses stepped out and approached Sona.

"President, the preparations are complete. We're ready for your final review," said Tsubaki Shinra, Sona's Queen.

"Understood. Thank you, Tsubaki," Sona replied, standing up to leave with her.

"Sona, are you leaving already?" Rias asked.

"Yes, I have some matters to attend to. I'll leave you and Seekvaira to your discussion," Sona said, stepping into the teleportation circle with Tsubaki.

Before Sona disappeared, Rias quickly asked, "Sona, one last question—what has Akira been up to lately? Koneko and Gasper mentioned they haven't seen him much."

Sona paused, the teleportation circle glowing around her.

"Akira? He's been… busy. You'll see him soon enough."

With that, Sona and Tsubaki vanished, leaving Rias and Seekvaira to continue their conversation.