I don't own Highschool DxD or Kamen Rider and they belong to their respected owners.

Issei didn't think they'll lose if he and Rias' peerage would be able to defeat Shalba but he was too powerful. Even with his DoGaBaKi Form wasn't enough to stop him and that was his power form. Issei doesn't know how his life came to fight devils and angels, fighting Fangire was one thing but this was another level.

Issei would mostly stay home at try to make a violin that is amazing as his late father but he could never get it right. Sometimes he would go to school but he was too afraid that someone will learn about him being half-fangire.

He wasn't a social person but he was persuaded by Raynare, a sweet and rather attractive young schoolgirl. But her true colors were shown and she almost killed him. Rias arrived to save him and make him into a devil but Issei didn't want that he didn't want to lose his humanity, the reason he kept fighting the Fangires. Luckily Kivat brought Jiro to take him back to heal him.

Issei's thoughts were interrupted at he heard Kiba scream in pain and looked up to see Kiba as Ixa being thrown back by Shalba.

"Gah!" Shouted Kiba as he de-henshin from his Ixa Armor.

Issei got back up and charged towards Shalba, Kiva went for a punch but the Pure-Blood Devil caught the fist before punching Issei on the stomach multiple times before throwing him on the ground.

"Hmph, I thought this Kiva was powerful with him dealing with Fangires, Devils, and Fallen Angels, but it seems I was wrong," Shalba said. "I didn't even need to use my magic on you."

Shalba then walks towards Rias and grabs her by the throat choking her.

"Rias-san!" Issei shouted.

~/~

Back in Castle Doran, the three Arms Monsters were drinking tea and was about to play poker.

"Nothing like tea to ignore some aches and pain," Jiro said as he sips his tea.

As Riki was passing the cards the castle had begun to shake and the lights were turning red and a tune was being played.

"Nani? What is that sound?" Ramon asked.

Tatsulot… is activating," Rikki answered.

"He's reacting to Kiva's feelings," Jiro said.

~/~

Issei charged forward and grab Shalba by his cape pulling it which made the Devil let go of Rias. Issei pushes Shalba back and tried to hold him down by his wait but it just gave Shalba the opportunity to elbow him on his back.

The elbow on the back sends Kiva face-first to the ground. Shalba began to stomp on the Half-Fangire's back multiple time sending sparks. Shalba walks back to Rias but even with the pain Issei got back up grab hold of Shalba's cape but Shalba pushes Issei's arm away. Shalba created a magic circle and shot a blast at Kiva sending the Rider crashing to a tree.

"Ugh," Issei groan in pain.

"Issei, you have to get up!" Kivat shouted.

~/~

Back in Castle Doran the ceiling suddenly burst open as something flew out of it. It looked like a small golden dragon known as Tatsulot.

"Tada!" Tatsulot shouted. "Time for my dramatic entrance!" He said as he flew around the three Arm Monsters before flying off to help Issei.

~/~

"Stop it…" Issei struggled to get up and stop Shalba.

"Pyunpyuun!" A voice got everyone's attention. They turn to the source to see a small golden dragon flying towards Issei. "Tension fortissimo!"

"Wh-who are you?!" Kivat question the new arrival.

Tatsulot swooped down and broke the chains holding Kiva's shoulder armor. They then unfolded and became golden bat wings. The sky turned black as a red full moon rose in the air. The wings also released a swarm of golden bats.

Shalba turned, shocked, and Risa watched equally surprised. All of Issei's friends were shocked as they see his new transformation.

Tatsulot flew around Kiva and the Rider raised his left arm, allowing the dragon to attach to it.

"Henshin!" shouted Tatsulot as the golden swarm returned.

The bats first covered Kiva's legs in golden boots with silver feet that had blades on the back of the ankles, then his torso armor turned to gold with a red chest plate resembling the unsealed state of his iron boots. He also gained golden gauntlets. Finally, the bats enveloped his helmet, turning his visor red with extra red fangs, trimmed in white with a golden crescent moon ornament resting on top where the bat head was. The mouthguard had also become pitch black. His shoulder armors were now spiked and Kivat's eyes were now a mixture of red, blue, green and purple. Finally, with a wave of his left arm, flames burst from his back and became a blood-red cape. This Kamen Rider Kiva Emperor Form.

"T-this power?!" Shalba muttered to himself. "It can't be. This power is similar to Dark Kiva."

"Issei…" Risa whispered awe.

"Woah, all that gold makes Kiva look like a king," Yuuto commented.

"He looks more like an emperor than a king," Koneko says.

Issei lets his cape flow before he charged towards the devil. "Shalba!" shouted Kiva as he punched Shalba across the face. He punched Shalba in the gut. Kiva used a snap kick to send Shalba reeling back. "That was for hurting my friends!"

Shalba created a magic circle and launches an attack at Issei but the golden Kiva covered himself with his forearms which easily blocked Shalba's attack shocking the devil.

Kiva walks towards Shalba and grabs hold of him before giving Shalba multiple sidekicks making Shalba tumbled on the floor.

"And this is for hurting Rias-san!" Shouted Kiva as he raised up Tatsulot and tugged the head, allowing the image under the window to spin and stop at his emblem.

"WAKE UP FEVER!" shouted Tatsulot as Kiva was surrounded by a red aura. He trained his eyes on Shalba's charging form before leaping upwards. He then executed a dropkick as the aura formed energy blades at his feet shaped like pick-axes.

Issei was slammed in at Shalba's chest, Kiva then started kicking him wildly, the blades doing additional damage as they hacked and slashed at the Astaroth heir. The devil screamed as he was pushed by Kiva's bicycle kicks.

"Haaahhh!" shouted Kiva kicked him all towards a tree before flipping of him and stared Shalba right in the eyes.

"Impossible!" Shalba clutched his chest. "To be defeated by a mortal half-breed! Just you wait, half-breed, this won't go unanswered!"

Issei looks at one more time before walking away as sparks appeared on Shalba's chest before falling face-first and exploding. Issei didn't look back as he walks to his friends' check on them but he knew killing Shalba would go unanswered but no matter who comes at him knew his friends will be by his side.