The Lagoon Heiress.
"Yukio? You know where that came from?" - Issei asked, confused as to what he was seeing.
"I... I do, and at the same time I don't..." - the boy answered, trying to dig as deep as he could into his mind to find where the memory of that attack came from, yet he could only see the faint silhouette of a dragon with two heads in front of him.
While trying to remember what it was, someone landed in front of both him and Issei. It was a woman with short aquamarine hair, wielding light armor that looked like a dragon's scales.
"I sensed the power of the Dream Dragon over here, and it seems I was right. He found someone to give his powers to - the woman spoke while looking at Yukio - ``What's your name boy?" -
"Yukio... Who are you?" -
"Call me Kai'Sa, I'm the heiress to the power of the Lagoon Dragon, and for the longest time, I thought I was the last Dragonmancer. Quite the shock seeing another one of us alive" -
"Of us? What are you talking about?" -
"Dragonmancers, beings that inherit the power of dragons to act as their enforcers in this world. Many existed in the past, but their numbers died down over time until a handful remained. As for this era, I only know of you and me. For all I know, we could be the last Dragonmancers" -
"And what do you want my Pawn for, Kai'Sa?" - Sona asked, curious about the woman's intentions - "Appearing out of nowhere like that was quite the surprise" -
"You can relax, I'm not interested in a fight. I was curious about sensing another Dragonmancer close" -
"Well, here I am in the flesh. Do you want something else?" -
"Not really. I will be keeping in touch with you Yukio, so you better be ready to see me often" - as she said that, she turned her eyes towards Issei while surprising herself - "Oh my Ophis, is that really a Dragonmancer for Ddraig?" -
She got up and close in Issei's face while she examined the gauntlet in his arm - "Hey Ddraig, are you in there? According to the Lagoon Dragon, you were always against the idea of using Dragonmancers to do your bidding, what changed?" -
The green gem in the gauntlet started to shine and a voice came out of it - "You think this was my choice? I never wanted this, but my original body was destroyed and I ended up like this" -
"Oh, that's a bummer. Lagoon said that she wanted to have a duel with you if she ever met you, but I think that can't be- Wait, I can have a duel with your Dragonmancer!" -
"Wait a second, you think you can come up here and challenge my Pawn to a fight out of nowhere? Who do you think you are?" - Rias got into the conversation immediately.
"This is Dragonmancer business, stay out of this" - Kai'Sa answered without even looking at the Gremory, who in turn answered with a shot from her Power of Destruction, pushing Kai'Sa away.
"Oh, so that's how we're doing things... Fine by me" - Kai'Sa formed in her hands what seemed to be two water projectiles and fired them against Rias, with her blocking them with her own power. Kai'Sa didn't stopped there however, as she continued attacking with incredible speed until a Dragon Shot from Issei pushed her away - "Isn't this fun..." -
"You're not hurting the President while I'm here, I won't allow it" - Issei yelled while preparing his Boosted Gear for another attack if necessary.
"Quite protective of her aren't you? Fine, I won't fight her, but I'm not leaving unless either of the two fight me" -
Issei and Yukio both shared a look before getting into fight position in front of Kai'Sa - "Oh, s 1? Fine by me, make it interesting" -
Issei attacked first, using his Dragon Shot to force their enemy into the defensive and allowing Yukio to close up, almost hitting Kai'Sa, yet she dodged and attacked with a point blank water projectile which pushed the boy back. She kept attacking until Issei punched her and sent her flying a few meters away before checking in on Yukio.
As the boy got up, they both listened to the steps of Kai'Sa moving around them, yet they couldn't see her.
"Can she turn invisible?" - Issei asked as he and Yukio got back-to-back.
"Listen to her steps, we don't need to see her to... Agh!" - before the boy could finish speaking, someone punched him in the face and sent him, and by extension Issei, flying. Kai'Sa then turned off her invisibility.
After seeing that, Sona got into the fight, summoning pillars of water from underneath Kai'Sa to launch her into the air, where Rias followed with a blast from her Power of Destruction.
The Dragonmancer of the Lagoon Dragon fell to the ground wounded. The Power of Destruction was devastating, even to someone like her.
"I could work with the 2 v 1, but not with the 4 v 1" - she said while slowly getting up - "Dream Dragon, Red Dragon, you both have great potential, but you need to unlock it first" -
"What the hell are you talking about?" - Yukio asked.
"Every dragon has secrets. To unlock their full power, one must first learn of them. I'm still doing so, but the results can be seen already" -
She then turned to look at Yukio once more before shooting a small smile - "You know? You remind me of your sister" -
"Huh?" - the boy said, as he got close to Kai'Sa - "I don't have a..." -
"You do, but Truth told her that she needed to stay away from her family to continue her training. Maybe, if you go on this path for long enough, you'll meet her once again" - she said, before walking away and starting to disappear in a whirlpool - "We'll see each other again. Dream, Red, I'll be looking for the rematch, so you better become stronger before I come back" -
And thus, Kai'Sa was gone, leaving Yukio with a single thought in his mind.
"I have a sister..." -