While Rei was in the Nasuverse, the others were still in the DxD world, specifically in the Zero Dimension where they had gathered.
Days had passed since Rei had suddenly disappeared during a meal. Initially, Rias, Koneko, Ingvild, and even Ophis panicked. However, Djeeta reassured them.
"There's nothing to worry about. Someone must've summoned him, probably one of our friends in the Sky Realm. They're the only ones who know how to summon Rei," she explained.
Soon, Lyria received a message from Rei, saying that he was in another world again. Apparently, someone from there had managed to summon him for some reason.
"Is it really that easy to summon Rei? How could someone from another world summon him?" Rias asked.
"It's not easy," Lyria clarified. "They need a specific catalyst and also know our language."
"But how could someone not from the Sky Realm manage to summon him?" Ingvild asked, confused.
"Probably someone we know who accidentally ended up in the Sky Realm," Sturm suggested.
"Oh, right. That makes sense," Djeeta said, recalling past events. "It's been a while since people started appearing in the Sky Realm again."
"Eh? What do you mean?" Koneko asked, tilting her head.
Djeeta and the others explained how, in the Sky Realm, people from other dimensions often ended up there, usually due to primal beasts' powers or because Bahamut never repaired the dimensional barriers. This allowed people to enter randomly.
"Yeah, I remember that slime girl who came to our world. She was so squishy and comfortable to hug," Lyria said, reminiscing.
"Wasn't that slime genderless?" Sturm asked.
"At first, but Rei played around and changed her gender to female. He even added restrictions so Raphael couldn't undo it," Djeeta said with a laugh.
Before Rimuru, the slime, returned to her original world, Rei had placed a curse on her as revenge for eating all the food on the Grandcypher. He had called it a harmless prank that would wear off eventually.
"And then there was that silver-haired samurai with the wooden katana. That guy was weird—he kept complaining about Rei's power and being jealous of his harem," Lyria added.
"Yeah, but that was fun too," Djeeta replied, laughing.
As Djeeta, Lyria, and Sturm recalled their adventures, Rias, Ingvild, and Koneko listened quietly.
"Your world sounds like so much fun," Ingvild said with a smile.
"Not really..." Djeeta replied, her voice grim. "We have a lot of enemies, and their powers are overwhelming."
"There were so many times we didn't know if we'd survive, let alone stop them," Lyria added solemnly.
Their words left Rias and the others silent. For people as strong as Djeeta, Lyria, and Sturm to describe their enemies as terrifying was deeply unsettling.
"But enough of that kind of talk," Sturm said, clapping her hands. "Do you want to ask anything else about the Sky Realm?"
Ingvild hesitated, clearly wanting to ask something but unsure. Koneko, however, spoke up.
"How many lovers does Rei have?" she asked, her cat ears twitching and her three tails swaying.
"Eh!?" Ingvild was shocked, clearly surprised by Koneko's question.
"Lovers, huh..." Lyria pondered. "Let's just say he has a lot. From Primarchs to Primal Beasts, even humans—he's got so many you'd lose count."
"Yep, but I'm the first one!" Djeeta declared proudly.
"No, I'm the first one," Lyria retorted.
"I was the first to meet him, so I'm his first lover!"
"That doesn't count. It's about who's been with him the longest."
"Well, by that logic, it's Ferry and Tiamat. They've been with him since that incident," Djeeta replied smugly.
"That doesn't count either—it happened in a dream!" Lyria snapped back.
The two began bickering, leaving Rias and the others bewildered.
"Sigh... Let's move somewhere else if you have more questions," Sturm said, standing and heading to the backyard.
Rias, Ingvild, and Koneko followed her, still curious about Rei and the Sky Realm. Ophis silently followed from behind, while Fenrir remained asleep beside Djeeta and Lyria, who were still arguing.
------
After Rei returned the Gateway-Star Sword, Lyria immediately took it and sealed it within her body.
She needed to ensure no one else could use the weapon, keeping it safe because the Celestial Weapon Series was far too powerful for a normal world.
"Pyuh... I didn't expect Rei to use this. What exactly happened in that world?" Lyria murmured to herself.
"Um, Lyria, are you okay? You suddenly acted... mechanical," Koneko asked, her voice tinged with worry.
Considering how Lyria had been chasing her moments ago for a hug, only to stop and start speaking strangely, anyone would feel concerned.
"Yeah, I'm fine. Something just came up. I need to see Djeeta," Lyria replied with a reassuring smile, patting Koneko's head before walking away.
Koneko, still curious, decided to quietly follow her.
Lyria walked through the corridors of their house, heading toward the main room where Fenrir was watching TV with Grisella, who had stopped by.
"Hello, you two. Did either of you see where Djeeta and Rias went?" Lyria asked.
"Hmm? Djeeta and Rias are training over by the lake," Fenrir answered, glancing briefly at her.
"I see. Thanks, Fenrir," Lyria replied, about to leave before Grisella stopped her.
"Wait, I want to come too~," Grisella said with a smile, quickly joining Lyria and Koneko.
As they walked, Grisella decided to ask about the power she had felt a few minutes earlier.
Lyria explained that it was the power of a Celestial Weapon Rei had summoned and that she now needed to inform Djeeta about it.
"Celestial Weapon...? If I may ask, what kind of weapon is it?" Grisella asked, her curiosity piqued.
"…It's hard to explain. That weapon is one of our transcendent weapons, filled with the power of stars and boundary Power. We don't fully know its capabilities because we've never used all its power," Lyria explained hesitantly.
Even Lyria and Djeeta didn't fully understand the true extent of the Celestial Weapons because they rarely used them, only in the direst situations.
For them, their own strength was usually sufficient, so it was strange for Lyria to see Rei using it.
The Gateway-Star Sword was capable of slicing everything and anything in half, and the other Celestial Weapons in the series possessed equally overwhelming powers.
"That's... excessive," Koneko deadpanned upon hearing the explanation.
"Haha, well, that's just how things work in the Sky Realm," Lyria said, shrugging.
Eventually, they arrived at the training site.
The first thing they noticed was the lake—or what was left of it. The once-beautiful lake was now completely destroyed. Its waters had vanished, leaving behind craters and shattered trees. Everything was in ruins.
Nearby, Rias stood with her clothes nearly shredded, her body covered in wounds, yet she still held the Bahamut Sword tightly in her hands.
"Hahh… hahh…" Her heavy breathing made her exhaustion evident.
Djeeta stood beside her, examining her condition.
"You're getting the hang of the Bahamut Sword. It won't be long before you can actually control it," Djeeta said proudly.
"Of course… I can do it… if I put my mind to it…" Rias replied, panting heavily.
Djeeta immediately healed her, restoring her body and replenishing her demonic power.
Rias could feel her strength growing. With each training session, her power increased, and now, she was far beyond her usual self.
"Rias, looks like you're working hard," they heard Lyria's voice as they turned to see her group approaching.
"Oh, Lyria? What brings you here?" Djeeta asked.
Koneko quickly ran to her Buchou, checking her condition. "Are you okay, Buchou?"
"I'm fine—no, I feel amazing!" Rias exclaimed joyfully.
"This sword just feels… incredible. Every time I swing it, it's… indescribable," Rias said, showing the Bahamut Sword at Koneko.
Koneko, however, had no idea what her Buchou was talking about. Everytime she touched the Bahamut Sword, it immediately absorbed her senjutsu, leaving her dizzy.
Even now, the malicious aura of the sword was enough to make her step back uneasily.
"Oh, sorry! I forgot this sword makes you uncomfortable," Rias said, dismissing the weapon.
The Bahamut Sword glowed, transforming into a small bracelet adorned with a miniature sword statue.
"So, Rei used a Celestial Weapon? Did he say anything else?" Djeeta asked.
"No, after that, there was no more contact," Lyria replied, shaking her head.
"Well, if it's just that, he's probably fine. Summoning that sword was probably just for show," Djeeta said casually.
"What happened?" Rias asked Koneko.
Koneko quickly explained everything before concluding Rias training for the day.
"By the way, is Ingvild still with Wamdus?" Koneko asked suddenly.
"Hmm? Yeah, she's still inside Wamdus' dimension training. It's been a few days now—looks like she's really determined to get stronger," Djeeta replied.
"I see… but I won't lose to her. Even with her Sacred Gear, I'll become an Ultimate-Class Devil first!" Rias declared with determination.
"…Um, Buchou," Koneko said suddenly.
"Yes, Koneko?"
"You do know that your current demonic power is already far past the requirements for an Ultimate-Class Devil, right?"
"Huh?"
"Ultimate-Class? What's that?" Djeeta asked, tilting her head.
"Ultimate-Class is a ranking system for devils in our world," Rias began explaining to Djeeta and Lyria.
Grisella, meanwhile looked around the place appearing uninterested to what Rias explained.
"Some sort of ranking? Is it similar to how we rank?" Djeeta asked.
"Yeah, it's probably the same principle—the higher the rank, the stronger and more important they are," Lyria replied thoughtfully.
"You know, you two don't really know much about our world yet, huh?" Rias asked.
"Not really. Lyria and I stopped going out because people kept asking us to join their weird cults, and when we ignored them, they attacked us," Djeeta said, clearly annoyed.
"I pity anyone foolish enough to attack you two," Koneko murmured.
"How about this let's take a break from training tomorrow. I'll bring you both and Sturm to our school and show you around," Rias suggested with a smile.
"It's been days since we've been back to school, and tomorrow's perfect timing since Koneko and I need to prepare for exams before summer break. Plus, I can introduce you to my peerage members!"
Hearing that, Djeeta immediately looked excited about Rias's suggestion.
"Are you sure? Yes, I'd love to! I want to see what schools are like in another world!" Djeeta quickly agreed.
"Hmm, sure, I'm fine with it too. There's nothing for us to do in this dimension anyway with Rei not around," Lyria agreed as well.
"What about you, Grisella?" Rias asked her.
"No, I'll skip that one. You know exactly what will happen if I go to the human world," Grisella said, shaking her head.
Unlike the others, Grisella disliked hiding her power. As a dragon, she wanted to take pride in her strength and display it openly to others.
"I see. Alright then, I'll let my other peerage members know later," Rias said.
After that, they returned to their house to rest and prepare for the next day.
Rias used her magic to contact Akeno, informing her that she would be returning tomorrow.