Male OC X Kimetsu No Yaiba / Demon Slayer

Swords, Demons and Twins

Oreki's POV

"Fire Style: Burning Rush." With the same seal sequence as the aforementioned Jutsu, the dragon, ox, and hare are added at the end and the technique changes from defensive to offensive. As the customary sphere surrounding me appears to fade out, it instead sweeps back and wraps itself around me in the elemental shape of flames at the arms and shoulders. At this, I find myself temporarily invigorated. This Jutsu is both defensive and offensive, both blocking attacks and acting as one itself. The secondary effect here is that I can move at a slightly more increased speed than usual alongside the actual flame effects that obviously harm opponents upon contact.

"Second Form: Pearl Flowers Moongazing." Kokushibo performs several slashes while sending a barrage of chaotic blades forward, cutting through my fire.

"Fire Release: Aerial Explosion Technique." This Jutsu releases a gas into the air. This is an odorless, colorless gas that can be ignited with any spark or flame. This gas will rapidly ignite, causing it to expand and create a strong wind in all directions. The outer gas is shot out and ignites when it has expanded at a range of around 20 feet. Anyone within the range of this Jutsu will be seriously injured and probably suffer at least a first-degree burn. It also evaporates all water in the range of this Jutsu. After I released the gas, I made a spark with my kunai knife and sword. A wide range of explosions occurs, but I know that this is still far from over. His regeneration really is something.

"Sixth Form: Perpetual Night, Lonely Moon - Incessant." Kokushibo releases a wild storm of slashes in multiple directions. This technique was powerful enough to not only slice up multiple around him but also overwhelm the Wind Hashira according to the original plot.

"Fire Release: Flame Sphere Technique." Quite different from the other various Katons in Leaf's arsenal, this one instead is a defensive Jutsu. Quite easy to learn, it is also performed much differently from other Jutsu. Using the body as a heat source, I mold chakra to amplify it and make it entirely visible. Then I expand it, using more chakra, and take on a red, spherical shape. This shield is used as a defense against both ninjutsu and taijutsu. It isn't very powerful, though, and can only parry at most one technique before deactivating. A drawback to this Jutsu, though, is based on the body's temperature. If the user performs this technique late in a fight they risk fainting due to both a drastic change in body temperature and already stressed body levels. Plus, the user of this Jutsu must remain still while using this technique. This shield manages to block his assault.

Noticing me not moving, he immediately plan out the next move. "Eighth Form: Moon-Dragon Ringtail." Kokushibo uses a direct frontal attack that creates a single gigantic slash, coming right at me. I side-stepped to dodge it since the distance benefited me. He follows up with another attack. "Ninth Form: Waning Moonswaths" Kokushibo creates a seemingly endless stream of slashes, capable of cutting down his intended target from a long-range.

When the attack almost reaches me, I shunshin to his right. His reaction is quick. Both of our swords clashed at the very moment but unfortunately for him, I got hidden cards under my sleeve. "Fire Release: Longsword Technique!" I focus all heat around me onto my skin. Then, by molding chakra in the most precise manner I'm able to turn my entire arm, the most dominant usually, into a long, flaming sword. It shoots out from the arm and remains there for a few moments, incinerating anything it touches. It is basically amplified to the point where it can be used offensively. With that technique, I stab his abdomen.

"...You pierced me with your arm... not with nichirin weapons. Quite a monster you are. Aren't you lucky to be born strong?" Kokushibou spits out blood. That flimsy wound I inflicted won't kill him so of course, he's fine.

"When you're weak, people make fun of you and even bully you. When you're strong, they call you a monster. In the end, these two ended up in loneliness. Won't you agree, Kokushibou?"