My offer hung in the air like a storm cloud. To help them train. Not out of pity, not out of nobility. But from a mix of boredom, irritation at that peacock Phoenix, and a purely scientific interest—could this ragtag bunch of demons and one lost nun actually gain any strength under the pressure I was about to inflict? Ten days. Ten days until the Rating Game that would decide Rias Gremory's fate. Ten days to turn them from potential victims into... well, at least into slightly less easy prey. And ten days for me to not die of tedium. The deal seemed perfectly acceptable to me. For them—a phantom chance. For me—entertainment.
Day One.
We teleported to one of the training dimensions available to the Gremory clan. Rias, using her connections and probably her Satan-brother's help, had arranged access to a vast space—a rocky valley surrounded by mountains, under an artificial, dimly lit sky. The perfect place to be loud, to break things, and to scream in pain without attracting the attention of the human world.
I looked over my "charges." They stood before me—Rias, Issei, Kiba, Akeno, Koneko, and Asia—pale, tense, but with a fire of determination in their eyes. Even Asia, though hiding behind Rias, watched with a kind of desperate hope. Pathetic. But ready for the worst.
"Alright," I began, my voice echoing off the cliffs. "The rules are simple. There are no rules. There is only one goal—get stronger in ten days. Strong enough that you have at least a one-in-a-thousand chance against Riser and his harem. I'm not going to teach you magic or swordsmanship—you have your Queens and Knights for that. I am going to break you. Push you to your limits. Force you to work until you're coughing up your own lungs. Don't expect pity. There will be no mercy. There will only be pain, sweat, and maybe a little blood. Anyone who can't take it can crawl away right now. The rest of you—prepare for the worst."
I swept them with an icy gaze.
"Your main problem is that you're weak. Not just physically or magically. You're weak in spirit. You rely on your titles, on your Sacred Gears, on your Queen. But when a real fight comes, all of that might be useless. You need to learn to survive. To think faster. To react instantly. To use your abilities not by the book, but based on the situation. And most importantly—to not give up, even when it seems like it's all over."
I paused, letting them absorb my words.
"Each of you has your own strengths and weaknesses. I'll create individual programs for you. But often, you'll train together, getting in each other's way, creating chaos. Because a fight is chaos. And you must learn to act within it. Asia,"—I turned to the nun, who flinched at my gaze—"your job is to patch these idiots up. Quickly, efficiently, without getting distracted by the noise and explosions. Your endurance will be tested just as much as theirs. Got it?"
Asia nodded fearfully, clutching her hands to her chest.
"Excellent." I clapped my hands. The sound was deafening in the valley's silence. "The show begins. Kiba! You're first."
Kiba Yuuto (Knight): The Dance on the Edge of Speed
I stood opposite Kiba. He was fast, elegant in his movements, his Sword Birth allowing him to create blades from thin air. But his speed was… predictable. Demonic, yes, but still limited.
"Your problem, Knight," I said, stretching my neck, "is that you rely too much on your 'innate' speed. You're fast by demon standards. But against a truly fast opponent, you're a turtle. Your task is to learn not just to move fast, but to react to a speed that's beyond your comprehension."
And I attacked. Not with my fist, not with magic. Just with movement. I vanished, reappearing to his right, his left, behind his back. My speed was such that he only saw blurs, felt only the currents of air where I had just been. I wasn't striking. Not yet. I was just "dancing" around him, not letting him focus, not letting him predict my next move.
"Where are you?!" Kiba shouted, instinctively thrusting a conjured sword out.
"Everywhere. And nowhere," my voice came from somewhere above. I hung in the air for a fraction of a second before vanishing again. "Your eyes are useless. Your senses are lagging. You must anticipate. Get ahead of me. Think, Knight! Where will I appear next?"
I lightly tapped his shoulder. He spun, slashing his sword through empty air. I was already behind him. A light push—he nearly fell.
"Too slow!" I yelled. "You're reacting to what already happened! You must react to what's about to happen! Use your Sword Birth! Don't just make swords in front of you, make them around you! Create a danger zone! Force me to respect your blades!"
Kiba, gritting his teeth, followed the advice. Demonic swords began to appear around him—dozens of blades, spinning, shooting out in all directions. The space around him became dangerous.
"Better," I nodded, continuing my dance between the blades. "But not enough! Speed! Precision! Don't just scatter scrap metal, control it! Strike where I am not, but where I might be! Make me dodge!"
I began to land light, but sharp, blows. Taps on his arms, shoves to his back, leg sweeps. Every time he tried to block or counter, I was already somewhere else. His face was covered in sweat, his breathing ragged. He was fast, but I was faster by orders of magnitude.
"Are you only using demonic swords?" I asked, appearing right in front of him for a split second. "What about your other gift? The Blade Blacksmith? Holy swords? Or are you still afraid of them? Afraid of your past?"
That hit a nerve. For a moment, surprise flashed in Kiba's eyes, quickly replaced by anger and pain.
"None of your business!"
"IT IS MY BUSINESS!" I roared. "As long as you refuse to accept your full power, you'll be a weakling! Your fear is your greatest weakness! Use the holy swords! Surprise me! Or die in this training!"
I increased the pressure. My movements became sharper, the hits more painful. I was cornering him, exhausting him, provoking him. I could see the fear and rage warring within him. I saw him trying to overcome himself. It was cruel. But necessary. To become faster than a bullet, you first have to learn how to dodge one.
Issei Hyoudou (Pawn): Stone Storm and the Dragon's Roar
"Your turn, Perverted Dragon!" I yelled, leaving the gasping Kiba to Asia's care. "Your problem is you're weak in body and mind. Your Boosted Gear is a powerful tool, but you use it like a club. No control, no stamina. You gas out quickly, and your attacks fly all over the place. We're going to fix that."
I pointed him to the center of the valley. "Stand there. Your job is to survive. And not just survive, but to build up power and attack the targets I point out. Ready?"
Issei swallowed nervously but nodded, activating his red gauntlet.
"Partner, be careful! His power... it's monstrous!" Ddraig's roar echoed in his head.
"I know, Ddraig! But I can handle it!" Issei muttered.
"'Survive,' huh?" I smirked. "We'll see."
I walked over to a scattering of rocks at the base of the cliff. My hands easily lifted several fist-sized boulders. My muscles tensed slightly.
"Let's start with a light warm-up," I said, and with inhuman strength and speed, I hurled the first stone. It whistled through the air like a cannonball. A second, third, and fourth followed... I wasn't using magic, just pure physics. But my physics could turn regular stones into lethal projectiles.
"Aaaah!" Issei yelled, barely managing to dodge the first stone, which slammed into the ground next to him, sending up an explosion of dust and leaving a small crater. He blocked the second with his gauntlet, feeling a massive jolt.
Stones flew from all directions, at different angles, at different speeds. I gave him no rest. Small pebbles left bruises; large boulders forced him to dodge desperately or block, wasting precious stamina.
"Don't just dodge, idiot!" I yelled, launching another boulder. "Build your power! Boost! Boost! Boost! You have to do it under fire! Don't lose focus! Think about where the next stone will fly! React!"
Issei, dodging a flying rock, roared, "Boost! Boost!" The gauntlet glowed brighter.
"Good! Now—targets! See those cliffs?" I pointed to three peaks on the mountainside. "Fire! Hit all three! Quickly! Before I turn you into a meat patty!"
"But... how?! The rocks... they're everywhere!"
"Your problem! Think! Move! Fire! Or die!" I picked up several larger rocks and launched them with twice the force. The sound of their flight was like the roar of a jet engine.
Issei scrambled around the field like a cornered animal. He dodged, blocked, yelled "Boost!", his body becoming covered in bruises and scrapes. He tried to aim, but the hail of stones disoriented him, not letting him concentrate. His first Dragon Shots went wide, slamming into the mountainside far from their targets.
"Partner, focus! Use my power! Feel the trajectory of the stones! Predict his throws!" Ddraig roared, trying to help.
"I'm trying! He's... he's too fast!" Issei gritted out.
He built up power again, twisted to avoid another stone that crashed into the ground, and fired. A red beam of energy struck one of the cliffs, shearing off a large chunk.
"Better!" I yelled. "But slow! And sloppy! Again! Faster! Build power faster! Shoot straighter! And don't forget to dodge! I'm not going to wait for you to aim!"
I scooped up a handful of sharp rock shards and threw them in a fan pattern. They whistled through the air like shrapnel. Issei howled as several shards bit into his leg and arm. But he didn't give up. Stubbornness, multiplied by fear and the desire to protect Rias, drove him. He yelled "Boost!" again, his eyes burning with desperation. He fired again and again, dodging, falling, getting back up under the hail of stones I threw with merciless precision and power. On the edge of the field, Asia was already preparing her healing magic, knowing this stubborn idiot would need her help soon.
It was brutal. But Issei needed to learn how to fight under pressure, to use the Dragon's power for survival, not just for show. He needed to get faster, tougher, and meaner.
Koneko Toujou (Rook): Unbreakable Strength and Fragile Control
"Small fry, your turn," I called to Koneko, as Issei—covered in bruises, scrapes, and small cuts—finally collapsed, and Asia rushed to envelop him in light.
Koneko approached, her face as impassive as ever, but her hazel eyes were tense. She was a Rook—the embodiment of defense and monstrous physical strength. But her power was untamed, instinctive.
"You're strong, cat," I said, looking at her tiny figure. "Very strong. But your strength is a sledgehammer. You can smash, but you can't control. You strike blindly. Your task is to learn to apply your power with precision, efficiency, and to be destructive only where it's needed."
I pointed to a massive boulder nearby. "See that? Shatter it. One punch. But don't just shatter it—do it so it breaks into three roughly equal pieces."
Koneko looked at the boulder, then at me. She nodded. She walked up, her small fists clenching. She reared back... and punched.
CRASH!
The boulder exploded into dozens of small fragments. A pillar of dust rose.
"I said three pieces!" I barked. "Not a pile of gravel! You just threw all your dumb strength into it! Where's the control?! Where's the precision?! Think, cat! Feel the stone! Find its weak points! Focus your power!"
Koneko frowned, her cheeks flushing slightly with annoyance. She moved to another, smaller boulder. She struck again, but this time her punch was different—sharp, focused. The rock cracked and split into four uneven chunks.
"Better," I admitted grudgingly. "But still not right. Again!"
And so it went, again and again. Koneko punched boulders, trying to complete my task. Sometimes she almost got it; other times, the rocks just disintegrated. I forced her to concentrate, to use not just raw power but the rudiments of Senjutsu she was learning—to feel the stone's energy, to channel her own power (Touki) precisely into the target.
Then I made it harder.
"Now, lift these fragments," I ordered, pointing to the multi-ton chunks of rock. "Lift them and hold them. Now, throw. But don't just throw—hit that specific rock on the slope."
Koneko, grunting with effort, lifted the giant boulders. Her small body trembled, but she held on. And then she threw them. The first throws were wild, missing the target or falling short.
"Harder! Straighter!" I yelled. "You're a Rook! Your strength must be not only destructive but reliable! Imagine you're protecting your comrades! You have to be a wall! Unbreakable and precise!"
Koneko gritted her teeth, her face covered in sweat. But she continued. Lifting, throwing, lifting again. Asia ran over from time to time to ease her muscle fatigue with magic. This was training at the very limit of her abilities, forcing her not just to use her power, but to understand it.
Akeno Himejima (Queen): The Lightning Dance and the Elusive Target
"Priestess of Thunder, your turn to shine," I addressed Akeno, as Koneko staggered away, exhausted.
Akeno smiled her signature "ara-ara" smile, but her eyes were serious. She was the Queen—a versatile fighter, master of both magic and physical combat. Her lightning was deadly, and her array of spells was a valuable weapon. But her problem was something else.
"You're not bad, Akeno," I said. "Your magic is destructive. But you're too... slow in its application. You rely on the power of your spells, but against a fast opponent, you're vulnerable. Your attacks aren't always accurate. You need to learn to strike fast, strike true, and with variety."
I stood in the middle of the clearing. "Your task is to hit me. With anything. Lightning, ice, fire—I don't care. Use your whole arsenal. But be warned... I won't be standing still."
And I began to move. Using my speed again, I moved around the valley erratically, unpredictably. I'd appear on a clifftop, a second later at the base of the mountain, then right behind her.
"Come on, Queen!" I taunted. "Impress me!"
Akeno began her assault. Bolts of lightning struck where I'd been a second ago. Lances of ice pierced empty air. Fireballs exploded, kicking up clouds of dust. She attacked furiously, her beautiful face concentrated, her lips pressed thin.
"Faster!" I yelled, easily dodging another bolt. "Your spells take too long to cast! I could have a cup of tea in the time it takes you to prepare! More precise! You're just firing blindly! Think! Predict!"
I appeared closer and closer, forcing her to change tactics, to switch from long-range attacks to close-quarters. She tried to catch me in magic traps, to create barriers, but I passed through them easily or simply vanished a moment before they snapped shut. Sometimes, I'd intentionally let her attack hit, allowing the lightning to touch me, and then... I'd annihilate it with my "Code: Unknown."
"What?!" Akeno was in shock as her most powerful bolt of holy lightning just... vanished, doing no harm. "How are you doing that?!"
"Trade secret," I smirked. "But that's not the point. The point is, you have to be ready for the unexpected! What if your opponent is immune to your main attack? What will you do then? Use other elements! Combine them! Be unpredictable!"
Akeno, biting her lip, began to experiment. Ice and fire, lightning and darkness. She tried to create complex combinations, to strike from multiple directions at once. This was more interesting. But I was still faster. I dodged, taunted, and forced her to go all out, pushing her to the point of magical exhaustion. Asia was on standby again, ready to restore her.
Rias Gremory (King): The Fury of Destruction and the Wall of Indifference
Finally, it was Rias's turn. She approached me, her crimson hair flowing in the wind, her eyes burning with a fire—a mix of determination and the wounded pride from my refusal to join the game. She was the King, the leader, the heiress to the Power of Destruction—one of the most formidable abilities in the demon world.
"Your power, Gremory," I said, looking her in the eye, "is pure entropy. Destruction. But you use it... inefficiently. You rely on its raw power, not control. Your attacks are too wide, too slow. You waste a huge amount of energy just to wipe something off the map. What if your opponent is fast? Or what if they have a strong defense?"
I held my hand out, palm forward. "Your task is to break my defense. Not kill me—you're not strong enough for that. Just... break through. Force me to take a step back. Use all your Power of Destruction. Show me what the heiress of Bael and Gremory can do."
Rias nodded. She focused, her body enveloped in a sinister crimson-black aura. The Power of Destruction began to concentrate in her hand, forming a sphere of pure annihilation. The air vibrated, and the stones at her feet began to crumble.
"Do it!" I commanded.
With a scream, she thrust the sphere forward. A powerful stream of destructive energy shot toward me. I met it with my palm. Not using "Code: Unknown." Just my physical durability and my aura.
BOOM!
The clash of two forces created a deafening roar. A shockwave rolled through the valley, forcing the others to stumble back. The sphere of destruction battered against my palm, trying to consume it, to erase it. I felt a colossal pressure, a burning, as if matter itself was trying to rip my hand apart atom by atom. But I stood. My hand was trembling from the strain, but I held.
"Weak!" I yelled through the roar. "More power! Concentrate! Don't scatter it! Hit one single point!"
Rias, seeing her attack had failed, roared in fury and desperation. She poured even more power into the stream. The aura around her grew thicker, darker. The sphere on my palm intensified, the pressure increasing. I could feel the skin on my hand start to crack under the pure entropy.
"Better!" I snarled, gritting my teeth. The pain was real, but bearable. "But still not enough! You can do more! Push past your limits, Gremory! Show me the fury of your house!"
She screamed, putting her entire being into the attack. The stream of destruction reached its peak. And I... I took half a step back. My defense had faltered. Not broken, but I'd felt the need to move, to compensate for the pressure.
The stream died. Rias was on her knees, panting, her magical reserves almost empty. She looked at me with surprise and... triumph? She had made me move. Only half a step, but she'd done it.
"Not bad," I said, lowering my hand. The skin on my palm was smoking and slowly regenerating. "You managed to budge me. But it cost you almost all your energy. Against Riser, that won't be enough. He'll just endure your attack and finish you. You need to learn to hit just as hard, but faster. And more often."
I walked over to her. "Again."
And the training continued. Again and again, she attacked, I deflected, criticized, and forced her to find new ways to focus her power, to push past her limits. Asia was there again, healing her magical exhaustion.
...
By the end of the first day of training, Rias's entire team was lying on the ground, strengthless. Their bodies ached, muscles burned, magical reserves were empty. They were more exhausted than they had ever been. Asia darted between them, her hands glowing with Twilight Healing, but she too looked pale and tired.
I stood over them, looking at the results of my "work." They were broken physically, but there was no despair in their eyes. There was fatigue, there was pain, but there was also... anger. Anger at me, at Riser, at themselves. And that anger was fueling their resolve.
"Day one is over," I announced. "Tomorrow will be worse."
I turned and walked away, leaving them on the battlefield I had created for them. Let them rest. They would need their strength. After all, there were still nine more days of hell to go. And only the strongest would make it to the end.