Shin and Tetsu stood in front of the vault door, with their body stronger than ever before. Their human and demonic bodies merged for a time, and the result was more than just the sum of their parts.
It was also truly shared now between its owners. Tetsu and Shin could control the body equally, but Tetsu didn't try to take the reins. Shin stayed in control, and the current form of their body reflected it.
For the most part, he looked the same as before. But he grew to the height he was used to in previous life, and metallic carapace with large red jewel covered most of his skin.
Shin flexed his—their—fist, getting used to the new strength. He pushed the vault door open. The thick and heavy steel construction moved with ease for a bit before hitting something on the other side.
Shin smiled, and put aside his box of books, turned and kicked the door HARD.
The door flew open, smashing the Red Painting that tried to break in and throwing it into the wall of the hallway.
Then the hybrid of demon and human jumped on top of it. Shin didn't even have to ask with words before Tetsu grew a set of long, jagged claws for their body to rip and tear.
"Hhha!" Shin shouted, stabbing them into the creature's body.
His first punch tore through its ribcage. When Shin touched something soft and pulsing, he pulled it open with a snarl.
It was a black and shriveled, but still beating heart, and the demonic part of it felt slightly hungry at the sight. The human part was mildly nauseated, but the adrenaline drowned out the feeling.
Shin threw the heart aside. The Red Painting still struggled, so he tore at its neck until he saw the spine. Then, in two quick movements, he grabbed the Red Painting's head and twisted it off the monster's shoulders.
The last beat of life finally was extinguished from that thing. And with such ease…
'You are so amazing, boss. That thing never stood a chance!' Tetsu purred. 'The blood pumping in our veins is such an intense feeling… Almost like eating. Is that how humans feel during fights? No wonder you fight so much, if that's the only way you can chase this… high!'
She sighed dreamily and sultrily. If normally Shin could mostly ignore her strangely lewd nature, now he felt not only her emotions, but her physical reactions.
They shared a body, after all. And when Tetsu was aroused—like right now—Shin was aroused, too. His pants felt too tight, even though his shirt was all sticky and gross with blood.
He wasn't going to deal with this. He. Was. Not.
Shin shut his eyes and pulled his body free from the merged state. The action took some effort, and then there was a second of that disturbing feeling of transformation.
Then he was only himself again. Not horny, thankfully. Still flushed and panting, but that was from the adrenaline.
'My friend?' Tetsu said from inside him, alarmed. 'What's wrong? Why did you split us? We were doing so well!'
Shin went back to the box of books. 'Yes, but we still only had two hands. I'm going to carry this box, and I trust you to fend off any enemies we might meet here, Tetsu. You should be strong enough now to do it, even without merging with me.'
'Oh, right. Of course, boss! Thank you for trusting my abilities! I won't disappoint you.'
Relieved that Tetsu accepted the explanation, Shin took the box and began running towards the exit. The last thing he wanted was being caught under a burning building.
If Mihara dies there, it would be all his fault for burning it in the first place. But Shin was still sure that Iashkawa would pull him out before it's too late.
Because of this, he didn't even think about searching for him and went straight for the exit. As soon as Shin and Tetsu reached the first storage floor, he saw another Red Painting stumbling down the hallway a few meters ahead.
Tetsu emerged from Shin and grinned. "Another one! I'm going to kill it quickly, partner."
"You better," Shin replied, hiding his nose with a sleeve.
Here, the smell of smoke was much sharper, and the temperature was high enough to make Shin sweat and crust the blood on his skin and clothes. It wasn't good.
The Red Painting noticed new enemies to destroy and began to move with a purpose. Instead of charging at it, Tetsu didn't move from her spot in front of Shin.
"I remembered one trick just now," she said. "Please, watch me closely, boss!"
Shin widened his eyes when pieces of her metal carapace suddenly flew off. Expanses of smooth white skin were revealed on Tetsu's shoulders, hips, stomach, and sides. All that was left was a pair of thigh-high boots, elbow-long gloves, a helmet and a steel bikini—the rest floated around Tetsu like a cloud of jagged daggers.
"Take this!" Tetsu shouted, pointing her hand at the Red Painting, and all that cloud flew at it with the speed of thrown daggers.
The force of the throw stopped the Red Painting in its tracks, but it wasn't the end. The pieces of metal kept moving, burrowing deeper into the creature's flesh, tearing it apart from the inside.
In seconds, the monster fell down, finally dead, and Tetsu returned her armor—now red with blood—back to her body. She turned to Shin and stared at him with an expectant grin.
"You saw this, huh? My armor is steel, so I can use it as a weapon if I don't have any other good metal around!"
Shin forced himself to smile back and look at her helmet, not anywhere else.
"Your magnetic manipulation grew a lot, Tetsu. That's really impressive. But you shouldn't use your armor this way if you can avoid it. It leaves you too defenseless."
'And too naked,' Shin thought, quietly enough for Tetsu to not hear.