"For now, wear this," Kousuke said as he handed Valerie a silver necklace with an intricate design cross. "it will at least hide the presence of your Sacred Gear to minimal, so only when someone is closer to you can they senses it's actually Longinus type."
He does have a way to completely disable it by cutting off her connection to it, just like the case with Gasper, although temporarily, until the latter learned how to control his emotion properly, or find a way to vanquish the fragment of Balor's consciousness without harming the Dhampir since Sacred Gear is tied to his soul. When Rias brings the topic about hiding Valerie from the devil who bought her from Tepes Faction, likely someone from Old Satan Faction, she immediately suggested turning the dhampir girl into part of peerage. But Kousuke rejected her suggestion, there's no need to be so hasty when the person herself still has some trauma toward the devil.
Then he came up with an ingenious idea, let Valerie borrowed his Ring of Transfiguration to disguise her appearance alongside an enchanted necklace to conceal the Longinus in such a clever way making others believe it's just a normal sacred gear. At this moment, Valerie stand at the same height as Gasper, but has dark blue hair instead of blonde. To completely hide her half vampiric trait, she changed her eyes color to light-blue—but this gives an unexpected results. When she stood next to Kousuke who was slightly taller than her, Akeno jokingly said the dhampir looks like his long lost forgotten little sister. This remarks brought faint blush to the dhampir's cheeks. Kousuke even entertained the idea by teasingly calling her little sister afterward, which only embarrassed her even more.
Issei suddenly fell to the ground on all fours.
"It should've been me! Not him!"
"? What's wrong with him?" Valerie asked with her head tilted to the side. Kousuke simply pat her head and said. "Don't worry about him."
"Now that her disguise are done, what about a fake name?" Akeno asked.
"Seele." Kousuke answered almost immediately. Because he was an Enchanter, he often had to comes up with names for his tools. After all, he can't just called them something like Mountain Slasher Sword MK-2.
"...That was fast, what does that even mean?"
"It means soul, quite suitable if you considered what her Longinus can do isn't it?" He replied with his hand on the dhampir's shoulder. "What do you think?"
"Seele...it's a nice name," Valerie, now Seele muttered with a smile. It seems she had taken a liking to the name. Even Gasper could be seen nodding in agreement, he was thankful he didn't have to come up with something because he wasn't good with names. His online gaming friends would agree to that.
"Well, there is still a much bigger problem at hand," Rias said with her hands clasped together as she rest her chin on top. "Where will she stay? Just for your information, my family's mansion is big, we have a few empty rooms available."
"She can stay at my place," Kousuke commented casually. "My parents won't be home for a while so it's just me, well, Morgan as well I guess."
"Plus, she might get kidnapped again if she were to stay here since no matter how much you tried to hide her, Old Satan Faction will eventually connected the dots." He continues. "On the other hand, they have less reach on the mortal realm, my house is also well protected, and my presence itself is the greatest protection she could ever ask for." He confidently said.
"You're taking that long lost sister plot a little too seriously," Morgan muttered with a teasing smile. She didn't think he would go after Valerie since the latter was clearly out of his strike zone. She knew him all too well to understand that, which was why she wasn't worried. But it's a different story for the dhampir, even now she could see a faint blush on the latter's cheeks. She needs to have some private chat with her later.
"Well, I can't deny that. I'm an only child of my family after all, so maybe deep down I wanted to have someone I can spoil," Kousuke said with a smile, his hand now naturally patting her on top of her head. He was just a little surprised that he even had some semblance of humanity left inside him. He thought he lost most of them in Otherworld, but fortunately he was wrong.
"I-I don't mind as well, I was also an only child so..." Seele mumbles, her cheeks reddened even more. She didn't know whether she was feeling embarrassed, or there was something more to it. However, it was undeniably that she enjoys being around him. 'Maybe this is what it feels to have a caring older brother...'
"Great, now that's decided, let's return to Kuoh," He said as matter of factly. "I don't think it will be good to stay here any longer since whoever locked her up should've realized something is up, the two Satans should gives us some time but better be safe than sorry."
"What? You're already going back?" Rias asked with widened eyes. She thought if Valerie stayed a bit longer in the mansion, she could persuaded her somehow. It's a Longinus after all, how can a devil let a chance slip right in front of her eyes? If Rias could have the dhampir in her peerage, she could easily top the rating game.
"Yes, the tour was fun, please tell that to your brother. He should understand that we can't stay here for too long." He replied.
"Nya? Then I'm going as well, see you later Shirone~" Kuroka said as she naturally stood up. She hadn't once stop trying to appeal herself to Kousuke ever since she changed side, but the latter easily shrugged her off as if her sexual charm did nothing to him. But she won't give up! It wasn't easy to find someone as strong as Kousuke, even Issei is barely passable. She doesn't mind the latter's perverted attitude, but his achievement and strength couldn't be compared to his friend. For Kuroka, those things are crucial for a good breeder.
"You know, you could just stand behind me instead of doing this," Kousuke said as he looks down and saw her arms wrapped around his waist, her ample chest pressing against his back. Morgan narrowed her eyes at this, a flicker of spark appeared at the snap of her fingers. Then suddenly, Kuroka let out a strange scream.
"NYAAAAOOW! W-What was that for?!"
"Oops, my apologies. It seems my power ran out of control again, tehee." Morgan said in a nonchalant voice. Kousuke simply shook his head at Morgan's trick, it only tickled him at best. But punishing him wasn't her goal, her target had been the cat burglar.
"Alright, enough with the cat fight, pun intended, we're going back so stay still or you might find a missing limb or two once the teleportation ends." Kousuke muttered with a grin. Valerie bid farewell to Gasper with a smile, it won't be like before where they were forcefully separated. She could meet him again later.
"W-What? That can't be right...on a second thought, I will stay with Shirone for n—" Before Kuroka finish her sentence, she was engulfed in his mana and vanished alongside him. Akeno simply giggles at her reaction, she wished she could followed him back but she was still training with Rias and her peerage. So she turned around and saw her best friend looking devastated as if her boyfriend had stolen something from her.
"Fufufu, you're bad at hiding your thoughts, Rias. He could read you like a book," She said with a chuckle. The latter widened her eyes in shock, she naively thought she had hidden it well.