A/N: Fair warning, Vanitas is a bit creepy. This story is a lot of fun to write!
Immediately, Ventus looked around, trying to find where Sora's body was, but Vanitas stepping even closer forced him to focus on him. If his arms were free, he would be able to punch him in the face at this distance.
"Where is Sora?!" Ventus demanded, "What did you do with him?!"
"You should know well where he is." Vanitas replied. Ventus glared at him and opened his mouth to retort but Vanitas just laughed at him, "Hehehahah! I didn't /kill/ him." He mocked, "It was an opportunistic time," He explained in his even tone, "His heart was in your body, and his sidekicks are seriously /weak/. I was able to take you and Sora away immediately."
"Where is his body, then." Ventus growled, since Vanitas seemed particularly chatty.
"Now you're asking the right questions. I left it behind with the duck and dog. I couldn't snatch that up, then you'd be able to revive him." Vanitas had a smirk in his voice. He was way too close. Ventus closed his eyes, gritted his teeth, and forced his magic on overdrive.
Vanitas jumped back as Ventus erupted into a beam of light, destroying the unversed that was holding him. Maybe it would have been smarter to be tied up until he figured out what in the world Vanitas wanted, but Ventus had enough.
The column of light flickered out and Ventus landed, taking wary steps back on shaky legs as he flung out his arm to summon his keyblade, Lost Memory. He looked for an exit, but all he saw in this place was blue and orange smoke and dozens of unversed. There had to be a way out!
"There isn't a way out of this, Ventus." Vanitas said matter-of-factly, "Come with me, unless you want us to demonstrate how weakened you've become after twelve years asleep." He took no battle position, but the unversed were closing in more tightly around them. Vanitas was serious.
Dread settled into the pit of Ventus's stomach. He had trouble /standing/, fighting was going to involve a lot of pain and falling over. A frown settled on his face. So be it! He would not surrender so easily!
"What do you want?! Revenge?!" Ventus questioned, glancing around at the unversed briefly. Which one was going to strike first?
"Revenge? No, idiot." Vanitas tilted his head at him as if he had said the sky was purple.
"Then what?! You know I won't forge the X-Blade with you! Do you want me to destroy our hearts again?!" Ventus spat.
"Forging the keyblade is inevitable." Vanitas replied easily, and at Ventus's continued glare he continued, "Master knows of a prophecy... seven lights and thirteen darknesses will clash and create the X-Blade."
"That's not going to happen! Not this... prophecy, nor am I going to be part of it!" Ventus quickly denied, and looked up at the sky. That was the only spot that was clear of enemies-
"Going somewhere?" Vanitas asked with a laugh in his voice, and Ventus slapped the pauldron on his arm. He closed his eyes as the pauldron shined and he was encased in his armor.
The unversed surged forward and Ventus threw his keyblade, which spun and flashed before turning into his hoverboard. He crouched slightly, gathering up his magic. The unversed's claws were inches away from him when he launched up and grabbed onto his hoverboard, which shot up into the sky. His exhilaration at the narrow escape was immediately pushed down when a large unversed surged ahead of him and a wave of dizziness made him crash into the creature.
Both the Metamorphosis and Ventus let out a cry of pain, but Ventus quickly recovered and jumped off the creature. His hoverboard caught him, and he had to kneel and grab the sides because the world was spinning too much. /No! Don't faint! I have to keep going!/ He screamed at himself, not trusting that Vanitas wouldn't kill him. He shot magic at the unversed that came too close, but eventually had to completely charge through as he focused completely on his speed. He was very grateful his armor was on, or else he would have been scratched by the unversed's spikes he slammed into. He knew the impacts would bruise and hurt like crazy later, if there was a 'later'.
Eventually, the corridor ended, he went out a black portal… and Ventus had to swerve to avoid hitting a black skyscraper. He slowed down, confused as to where he was, and that mistake had unversed tackle him out of the air. The edges of his vision went black when he hit the ground. Ventus's breaths quickened as he witnessed a flashback- this was just like the time those floods grabbed him when he thought he had defeated Vanitas. When Vanitas was just about to fuse with him. That sensation… his useless screams, he was shouting and calling his keyblade back to him, he never wanted that to happen again-
/Ventus! If you needed my help you could've asked me!/ Sora's voice broke through Ventus's panic, and strength flooded into his body. An faint apparition of him appeared, a hand touching his shoulder.
/Sora!/ Hope flooded into Ventus, and he reached for his magic again-
Cold metal against his neck brought Ventus's thoughts to a screeching halt, even as Sora continued to lend him power. Somehow, the unversed had taken off his helmet in his struggle and Vanitas had his keyblade under his chin. It wasn't /sharp/, but the threat was very much there. Unversed used Ventus's freeze-up to wrap around and restrain him to the ground, on his knees.
"I know you'll do anything for your values. Your pride." Vanitas said in a eerily gentle tone, tilting Ventus's head up to look at him, "But you're not the only one at risk here. If I destroy your body, then Sora would be utterly helpless…"
The despair and anger at such a proposition made Ventus flinch and truly stay still, his breaths coming in and out through his clenched teeth. Vanitas lowered his keyblade from him, and Ventus lowered his head, forcing himself to calm down with deeper breaths.
"Why are you so adamant that I go with you? Is the battle starting already?" Ventus tugged on his monster restraints, but they had a very good hold on him.
"That's not it…" Vanitas stepped towards him, and Ventus leaned back in dismay. To his surprise, Vanitas knelt to his eye level, "It's because you're completely insignificant. At the end of all this, there will be no one left to miss you…" Vanitas paused as Ventus growled, baring his teeth at him, "So I'm taking you away. You're mine."
"No! I'm /not/ yours!" Ventus erupted into light again, refusing to be broken, and Vanitas knelt in place and blocked the magic with his keyblade. He and his unversed were pushed away again.
The light faded into a colorful glow, and Ventus felt Sora's full support. In a mixture of nostalgia of a forgotten memory and the comfort of having his friend with him in such a dark place, Ventus held out both his hands and summoned two keyblades- one was Lost Memory, the other the Kingdom Key. Both he spun so they were backhanded.
"You've always gotten stronger when I've shown you mercy!" Vanitas laughed, "...I'll have to stop messing around and show you your place." His tone was low, determined now. His dark aura appeared, summoning more unversed to add to the dozens around them in these dark streets.