Issei is now Kamen Rider Ryuki with Booster Gear that has Red DragVisor on top of the gauntlet.
-deep within Issei's mind-
An eyes open for the first time after it's slumber. "My host has awaken me...? A surge of power is now flowing through his body....what an interesting host i have...", said the voice.
-currently-
Issei and Raynare Crow Smash now fighting against each other.
His hazard level is higher than that fallen angel and us. Your brother is indeed something.
"He have Boosted Gear within him. Of course he will be stronger me", said Ryusei. He then stare at Shark fullbottle and Motorbike fullbottle. "For now i have these, But I don't what to do with these", think Ryusei.
"Damn it! Damn it! Damn it! Damn it!!!!", shout Raynare. "That is not Twice Critical!! Its one of longinus sacred gear!! Boosted Gear!!", shout Raynare. Issei only silence as then he summon a sword after he take out a card from his advent deck and insert it into his DragVisor as he slash her multiple time. A last slash,open the gash of her body as green light hover our and enter Asia body.
Ryusei check Asia's breathing. She does not have much time, Ryusei. Our hope is whatever power that revives Issei 3 weeks ago.
"I just hope Rias and Akeno is here-"
Then a door of the abandoned church is open. Ryusei turn his head around to see Rias, Akeno, Kiba and Koneko.
"Ara? Ryusei is here? Hmm? Who is that? The one who fighting the fallen angel Raynare?", ask Akeno.
"That's Issei and that thing is call Crow Smash is the Fallen angel by the name Raynare", said Ryusei, carrying Asia body towards them. "I know you can bring her back. I trusted her to you. While Issei there is enrage to what happen to her, you can ease his sadness and rage by doing what you do to him", said Ryusei.
"You seem to know what we do, for a human. Who are you?", ask Rias. "I am just a big brother that caring for his little brother", said Ryusei with a smile. He give Asia to them as he then walk pass them.
"Now that is over, lets go home. We have much to do, Katsuragi-san", think Ryusei.
You don't want to wait for your brother?
"I figure they can handle it from now on", said Ryusei, walking to a distant.
-1 week later-
Issei told Ryusei that he is now part of Occult Research Club under Rias Gremory. Ryusei just happy for him. With power of Ryuki and Boosted Gear, Issei can be unstoppable against the future threat.
Project Hazard and the power-up for you?
"Yeah, Issei is now strong but Blood Stalk warn us about the other existence of kamen riders. I can guess that they will be using Sclash Driver made by your truly", said Ryusei.
Your theory is 50:50 correct but we don't know which driver will they use. If you right about the other kamen riders using sclash driver, we can begin creating Hazard Trigger and any power up item after that.
"Yeah but in the mean time, I have to come up the power up boost like FullFullBottle like how Sento create it. Hazard form is indeed a strong power up but I can't take a risk. Hazard Trigger is really dangerous", said Ryusei. Ryusei is now at his study desk, sketching Hazard Trigger with Full Full Bottle. He then remember something
"Katsuragi-san! Remember the event of Blood? Kamen Rider Blood? Where Queen of Mars has fuse Genius Fullbottle with gold and silver fullbottle, creating a device to defeat Kamen Rider Blood?", ask Ryusei.
I have...why? Wait, i think i know what you thinking. You want creating 'that'?
"That and imagine if its only Rabbit Essence and Dragon Essence only", said Ryusei.
Hmmm, interesting. Let's experiment on that....
-2 days later-
Ryusei now in the middle of a forest, testing the newly created device with a mold shape of can. Though he didn't insert the dragon essence yet.
"Okay, now to begin the experiment...", said Ryusei. he insert Silver Dragon Fullbottle and Gold Rabbit Fullbottle on the installation device with a thin tube going to the blank can. "Now, let's begin- hold on", he hide behind the large tree. "Let's begin the experiment", he said, as he click the button.
Both fullbottle essence is been secrete to the blank can as the red and silver essence enter the can as it glowing and shines.
Amazing...it's working....
As the shine fade, Ryusei saw the can has now the logo of CrossZBuild and the colour is red gold and blue silver.
He walk toward it, taking both the can and fullbottles as he inspect his new power up device.
"Superior CrossZBuild?", ask Ryusei, seeing the name of the can just below it.
Not realizing, A man are stalking Ryusei from afar. A smirk can be seen as he take out steam gun and insert Bat Fullbottle. Then he shoot a mist as the mist cover its body and forming a black armor auit. A symbol of a bat can is appear at his chest armor.
Ryusei then sense something going on as he summon his Drill Crusher turn it into a gun mode and shoot at the far left. A chuckles can be heard when a black armor figure comes out"Night Rogue...", think Ryusei.
I can guess Evolt gave the Transteam System to this guy...
Ryusei still in his civilian form, equip his Build Driver. "What do you want?", ask Ryusei. "Nothing, just checking what kamen rider are you...", said Night Rogue. "To be honest, the way that you are now is not really cant match Evolt", said Night Rogue. "You know him? Is he the one who gave you that system?", said Ryusei. "Well you can say that. He and I have mutual agreement to stay away from each other business", taunt Night Rogue.
That catch Ryusei off guard. "You sure?", ask Ryusei, confidently. "Yes, but i will not really reveal what is my name", said Night Rogue.
"I think i know...", think Ryusei. "And he is right. When Evolt using his kamen rider system, i will be outmatch in the future", think Ryusei.
"I think that is enough for now. I will see you soon, kamen rider...", said Night Rogue. Night Rogue fire a mist from his steam gun and vanish.
Ryusei look around and no Night Rogue around as he look back at his Shining Build Can. "Somehow, that guy feel familiar...", said Ryusei.
Be wary of that guy. Who knows he is gonna be an enemy in the future....
"Yeah..I'll note that..", said Ryusei
-end of chapter 5-