Phenomenon Breathing (Mitsuri Kanroji x Male Reader)

[Chapter Seven]: Advance Of The Anti-Phenomena: Overlord

"First of all, I don't even know you," Y/N growled at him, though he gripped the Tsuka of his blade tightly, like the Demon told him to. "Second of all... Phenomenon Breathing: Fourth Form! Nimble Actuality!"

And with that, he shot from the ground in an instant, zooming towards the Demon as he unsheathed his Nichirin Sword. His eyes were screwed up in concentration, fixed on the Demon's neck, his hands prepared to curve the blade and behead him. In only a few seconds, he'd already reached the masked Demon and was about to—

"Thirdly, shut your mouth," the Demon said nonchalantly, his large hand over Y/N's face, the other gripping the wrist that held the Nichirin Sword, which prevented him from attacking. Y/N struggled frantically, making noises that would've been screams had it not been for the hand over his mouth. "And finally...!" 

The Demon brought a powerful knee to Y/N's guts; it felt as hard as steel. He found himself tumbling back into the wall of the alleyway he'd collided with earlier. Y/N let out a scream of pain, shocked by the immense power behind the attack. It was unquestionably the strongest attack he'd ever had to sustain, and the power of this Demon when compared to all the others was unbelievably superior.

"Anti-Phenomenon Breathing: First Form. Fantasy Fixer!"

"There's no w—"

The Demon suddenly disappeared, leaving an afterimage and shocking Y/N. It reminded him of something, and if he was right in thinking that the Demon had similar Breathing Forms...! He looked around repeatedly. The Demon then appeared in multiple locations in the air: first to the left, then to the right, and finally in front of Y/N, before disappearing one last time. 

Instantly, knowing what this technique was, Y/N leapt from the ground and landed on a nearby house's roof, an eye kept on where he was going and an eye fixed on where the Demon was, which was, as he expected, right behind where he once was. His eyes widened when he spotted the Demon's hand on the Tsuka of his sheathed sword, his head facing down.

"So you're just a rip-off, huh?" Y/N noted angrily, as the Demon raised his head to look up at him. "But he can't copy the area's changing colours..."

"Nimble, aren't you?" the Demon asked, and Y/N had a good feeling that he was smiling sinisterly at him. "You're not your average Demon Slayer, especially not one that's just started."

Y/N looked around with one eye, the other still fixed on the Demon, trying to find Zion. However, no matter how far he searched, he couldn't locate the man, nor hear the sounds of his gun shooting. That sent a bit of panic coursing inside of him; had Zion possibly been attacked and killed by another Demon?

"Looking for your friend...?" questioned the Demon, who was now preparing to jump. Instead of preparing a counterattack, Y/N turned and began to sprint away, sliding down the diagonal structure of the roof in a stood-up position. "Interesting."

"Wait, what am I doing?" Y/N asked himself, in confusion, as the unmistakable sound of someone landing on the roof behind him filled his ears. "Why am I choosing to look for Zion when there's clearly a Demon to fight right here?!" He shook his head from side to side, refusing to believe that he was trying to find Zion. "I'm just... trying to create some distance between me and this demon; I know a lost cause when I see one... Yeah."

"Anti-Phenomenon Breathing: Second Form," came the Demon's voice from behind him. "Restricted Casualty!"

As Y/N turned his head, he spotted the Demon's sword shooting at him, spinning repeatedly in the air, the Demon's arm extended in a throwing position. He turned his full body around, and clenched his Nichirin Sword. Y/N reeled it back, as the Demon's blade came closer, and muttered, "Phenomenon Breathing: Second Form. Universal Hunter!"