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

The room was bathed in a soft, crimson glow as Akira stood before Gasper Vladi, his newly reclaimed familiar. The young vampire, with her golden hair and timid demeanor, stood at attention, her crimson eyes shining with determination.

"Alright, Gasper, from now on, you are officially my familiar," Akira declared, his voice calm yet commanding. He gently ruffled her hair and pinched her smooth cheek, a gesture that made her blush slightly.

"During the time I left you under Rias's care, did you train diligently?" he asked, his silver eyes piercing through her.

"Yes, Lord Akira!" Gasper replied, standing straight. "For your dream and to fulfill what I couldn't before, I've been training hard!"

Akira smiled, pleased with her response. He cast a quick appraisal skill to check her progress.

[Name: Gasper Vladi (♀)]

[Level: LV125 (Mid-tier High-Class Demon)]

[Attribute Evaluation]

[Note: Strength within the same level.]

Strength: D

Speed: C

Magic: C+

Durability: D

Martial/Technique Proficiency: C

(No talent for martial arts, but shows promise in vampire and dark-type spells.)

Sacred Gear/Bloodline Ability: SS+

Vampire Bloodline: As a half-human, half-vampire hybrid, Gasper possesses vampiric traits and abilities, such as transforming into bats and growing stronger by drinking blood.

Sacred Gear: Forbidden Balor View: A time-manipulation Sacred Gear derived from the power of the demon god Balor. It can freeze time within the user's line of sight.

Reincarnation of Balor: Gasper harbors the latent power of the demon god Balor. Her Sacred Gear is a manifestation of Balor's "Eyes of Death Perception." In extreme situations, she can summon dark beasts of the night, capable of bypassing even the strongest defenses and dealing irreversible damage.

[Overall Evaluation: SS-tier High-Class Demon.]

[Final Assessment: A vampire with limitless potential. Once she fully awakens Balor's power, she will undoubtedly become a top-tier powerhouse.]

"High-Class Demon strength... It seems you've been working hard, Gasper," Akira said, patting her head. Even without relying on his system, he knew Gasper's potential would ensure his success, even if he lost his status as a heir to the Leviathan clan.

He handed her a mutated Evil Piece, which glowed with a deep red light as it merged with her. The room was filled with an overwhelming aura as Gasper's power surged.

"This feeling...!" Gasper's eyes widened as her energy skyrocketed, breaking through to the Ultimate-Class Demon level.

Whoosh!

Ten demonic wings unfurled from her back, leaving everyone in the room—except Akira—stunned.

"Gasper, why do you have ten wings?!" Rias exclaimed. Ten wings were a sign of potential beyond even the Maou level.

"I-I don't know... I just felt this power surging within me, and then they appeared," Gasper replied meekly.

"And your current strength?" Rias pressed.

"Ultimate-Class Demon," Gasper whispered.

"Akira! What's going on?!" Rias turned to him, her voice filled with urgency.

Akira smirked, his expression calm and confident. "Rias, this is my newly awakened ability: Purification and Evolution. My Evil Pieces have evolved, allowing me to maximize the potential of my familiars."

He had no reason to hide this from Rias, as they were already allies. However, his true trump card—the awakening of his high-dimensional Leviathan bloodline—remained a secret.

"If your pieces have evolved... then Koneko can also—" Rias began, her voice trembling with excitement.

"Exactly. Koneko can unlock her true potential as well," Akira confirmed.

He turned to Koneko, who had been silently observing. "Koneko, are you willing to awaken your powers? If you're still hesitant about your Nekoshou bloodline, I won't force you."

Koneko's eyes hardened as she stepped forward. "Akira-senpai... I'm ready. Gasper is stronger than me now, and I trust her to stop me if I lose control. Besides, I believe in you. If you could guide Gasper and Agumon, you can guide me too."

She took the "Pawn" piece from Akira's hand. Moments later, her energy surged, reaching the peak of High-Class Demon level, on the verge of breaking into Ultimate-Class.

"Akira-senpai, I'll work hard to grow stronger. I won't hold you back," Koneko said, her competitive spirit ignited. The once-timid girl who bullied Gasper with garlic was now determined to catch up.

As Koneko completed the familiar contract, Akira heard the familiar chime of his system.

[Ding!]

[Congratulations, Host, for completing the sign-in mission!]

[Sign-in Level: Purple]

[Event: The White Cat Demon's New Master]

[Reward: 3 Pet Collars]

[Pet Collar Description:]

- A collar that reverses causality. The one who wears it becomes the host's pet, not the other way around.

- Can transform into any accessory, such as a necklace or pendant, or even become invisible.

- Note: The target must not resist when the collar is applied.

Akira stared at the reward, a mix of amusement and self-awareness crossing his face.

Well, I guess I'm fully embracing the role of a villain now, he thought. But if I'm going to be a villain, I might as well go all out.

His mind quickly began listing potential candidates for the collars:

Serafall Leviathan

Grayfia Lucifuge

Griselda Quarta

Gabriel

Roygun Belphegor

Not everyone could be bound by Evil Pieces, as they could be detected. The collars, however, were undetectable and perfect for securing key figures without raising suspicion.