It had been two full weeks since Castiel was last allowed in the Danger Room because of Illyana.
Every day, he followed a routine: he attended his regular classes, kept his head down, and at 7 p.m. sharp, made his way to Professor Xavier's office for his private lessons on social behaviour. The embarrassment still stung—how he slapped Illyana's butt that day, all because of a bizarre misunderstanding involving a pizza man on TV. But with Charles' help, he was slowly coming to terms with how much he didn't know.
He had learned a lot. About boundaries. About personal space. About why consent mattered. And definitely about how not to act around women.
Still… none of that fixed the fact that Illyana Rasputin hated his guts.
Every time she passed him in the hall, she gave him a death glare. A side-eye so sharp it could slice through steel. Castiel sighed every time. He had apologized. He knew he messed up. He just didn't know what else to do.
That night, he slumped onto his bed, arms folded behind his head, lost in thought. Colossus sat across the room, reading a book. Castiel turned toward him.
"Hey, Piotr… what do you think I can do to make Illyana forgive me?"
Colossus looked up, thoughtful. "Maybe a gift. She likes weapons. Or swords. You know, something unique. But... she's not easy to impress."
Castiel groaned. "Yeah, I figured."
"Sorry, brother," Piotr said with a half-smile. "You're on your own with this one."
Two more weeks passed. Castiel never missed a class. He became quieter, more introspective. Mr. Summers even told him privately, "You're doing well, Castiel. I think next week, you'll be ready to return to the Danger Room."
But something still lingered. That feeling in his chest every time Illyana glared at him. The guilt had faded into frustration. He made a mistake. A dumb one, sure—but he'd apologized. He was learning. Trying.
And she still looked at him like he was the devil himself.
So when he ran into her in the hallway that day—when she shot him that look again—something in him snapped.
"Illyana," he said.
She kept walking.
"Illyana," he repeated, stepping in front of her.
"What?" she snapped, her voice like a blade.
Before she could blink, Castiel grabbed her arm—and they were gone.
A swirl of white holy light, and they reappeared in the middle of nowhere. A vast, empty field beneath a gray sky. Wind swept across the open space. The silence was deafening.
Illyana yanked her arm back and summoned her Soul Sword in an instant. Its dark, twisted glow cut through the air.
"Are you insane?!" she shouted. "Teleport me back right now!"
"No," Castiel said calmly. "Not until we settle this."
Her brows furrowed.
"You're mad at me. I get it. I deserved it. But I apologized. I'm trying to learn. And I'm not going to keep tiptoeing around you while you act like I'm scum."
Illyana looked stunned for a second—but only a second.
"You kidnapped me here to lecture me?"
"No," Castiel said, his eyes glowing faintly. "I brought you here for a duel."
She raised a brow. "A duel?"
"We fight," he said. "All out. If you win, I'll do whatever you want. If I win, you forgive me."
Illyana's face twisted into a grin. "You're out of your mind."
"Maybe," he said. "But I'm done being treated like dirt when I've already done what I can to make amends."
She didn't hesitate.
"Fine," she said, stepping forward, blade raised. "Get your sword."
Castiel laughed. A low, amused sound. "I don't need it."
Illyana's grin fell.
"Today," he said, as the wind picked up around him, his spiritual wings starting to glow behind his back, "I'll show you the difference in power between us."
Illyana's eyes narrowed, and without another word, she charged.
Soul Sword raised. Rage in her eyes.
And Castiel stood his ground, holy light beginning to burn around him like the rising sun.
The field was silent, the grass swaying in the soft breeze, birds chirping lazily overhead. That silence didn't last.
With a single swipe of his hand, Castiel released a small shockwave of holy energy. It wasn't enough to harm Illyana, just enough to send her flying backward and land on her feet with a grunt. He raised his voice, calm but firm. "Do you surrender?"
Illyana spat something sharp in Russian, the tone clearly disrespectful, and vanished in a swirl of dark light.
Castiel didn't flinch—he felt her before he saw her. She reappeared behind him and swung her Soul Sword with intent. He turned and caught her with a glowing palm to the chest—a holy slap—that launched her back like a ragdoll, flipping through the air and crashing into the earth with a grunt.
Again and again she tried. She teleported, attacked from different angles, screamed in frustration, but Castiel was quicker, calmer, stronger. Every strike was met with a block, every shout answered by silence and a radiant counterattack.
Then it happened.
Illyana's body trembled. Her hands clenched. The Soul Sword pulsed with dark energy. Her eyes glowed crimson. The field's air thickened with heat and something older… fouler. Her body shifted—red skin, curling black horns, scales running down her arms. Her voice dropped several octaves and doubled in echo.
"You will regret humiliating me, angel!" she screamed. "Feel the wrath of the Darkchylde!"
The sheer force of the darkness surrounding her made Castiel's skin crawl. His wings twitched, glowing brighter in response. His halo pulsed as if readying itself for battle.
She swung her mutated Soul Sword, releasing a wave of corrupted energy. It screamed across the field. Castiel braced himself, raising both arms as a shield of light appeared before him. The reddish black and white energies clashed violently in a burst of light and shadow.
Smoke drifted into the air, but Castiel held steady. When the darkness cleared, Illyana rushed him again. Her strength was terrifying. She was faster, fiercer. But Castiel moved like light. He dodged a swing and unleashed a beam of white energy from his palm.
Illyana brought her sword up to block, but she was driven back, skidding across the field, heels digging into the dirt.
He didn't want to hurt her.
"I don't want to fight you like this, Illyana!" he shouted.
"You're not fighting Illyana!" she roared. "You're fighting me."
Suddenly, her hand twisted in the air, and the space behind her tore open into a flaming rift. A portal to Limbo.
The stench of sulfur and rot filled the air.
From within the swirling portal, demons poured out—grotesque creatures with burning eyes, snarling mouths, and twisted, leathery wings. They swarmed at him.
He had no choice.
He let go of his restraint.
Castiel's eyes flashed white. His wings spread wide and blazed with divine light. His halo flared so brightly it painted the whole field in daylight. When he raised his hand, the sky trembled.
"Smite."
The holy word rippled through the air like a wave. The ground cracked. The grass burned gold. The demons began to convulse, hissing and howling in pain.
Light consumed them—light so pure and furious they couldn't even scream before they were reduced to dust. The portal to Limbo trembled under the weight of Castiel's divine power.
Then it closed with a snap.
Silence returned.
Castiel dropped to one knee, panting. His skin shimmered with radiant energy, his wings trembling slightly. He looked up.
Illyana was lying in the grass, the demonic form gone. She looked… human again. Bruised. Burned. Alive.
Her breathing was shallow. Her Soul Sword lay broken beside her, dissipating into ash. Her eyes fluttered open, unfocused.
Castiel swallowed. "I'm sorry…" he whispered.
He approached her slowly and dropped to his knees beside her. He placed his hand gently over her heart, and with a glow of golden light, he began to heal her, softly, slowly, whispering prayers as he did.
The battle was over.
But the healing—of both body and trust—was just beginning.