Total Concentration: Devil Breathing (M!reader x demon slayer)

A Spiraling mess

With Y/n

Y/n: For what feels like days, though you have no way of telling time, you have done nothing but breathing while under the effects of a spell the demon called cull put on you. It feels like your ribs will be crushed and pierce your lungs if you don't breathe exactly right. Though it's not your most important problem, mastering this breathing technique seems to be your best bet at survival. Luckily there seems to be heavy rainfall outside or something of the like as has been water be through the ceiling and pooling in a raised in small hole in the ground. Not ideal for drinking water, but its water all the same. Though... you were never really hungry.

Flashback

Cull had said it was a stroke of pure luck we were stuck in a place that water naturally pooled in from.

Y/n: "We're located on a stretch of land between a mountain and an ocean. Even though it's the middle of winter, the weather warms up during the day so snow on the lower stretch of mountain melts and once it hits the ocean it evaporates. Blah Blah Blah water cycle and boom we have a long lasting rain shower and ice melt to fulfill our every water need."

Cull:"What perfectly boring answer "the devil sighed.

Y/n:"Yeah, well do you have anything better?" you droned?

Cull:"...Hmmph...ActUALly, I dO, would you care to hear it" he asked the static of his voice making a low whine. Not wanting to pass up the opportunity you nodded, trying to save your strength and focus on your breathing.

Cull:"I've come to feel that whenever we demons go to feast the rain comes to wash away the shed blood and sins we trek into the lives of others. The bigger the sins, the longer the rain shower...Now then the price for that answer is you drowning!"he laughed

Y/n:"W-WAIT WHAT!?"you screamed quaking in terror

Cull:"Relax ma boy I merely jest" his voice rasped and laughed. "Why would you pay for a completely wrong answer, it's simply preposterous!. Your first answer was completely correct, a dull lifeless answer for a dull lifeless world" He excitedly told you, his one visible arm out stretched like he was addressing a crowd. "That's what people like us are for ma boy!"

Y/n:"Wait...us" You mousely questioned him.

Cull: He retracted his arm and replaced it with a singular yellow eye, looking you dead in your own. "Yes, people like us. This world is boring, but I assure you when you leave this cave you will help me to turn it on it's head and give everyone the sense of exhilaration they don't know they need!"

Y/n:"B-but what if I don't get out of this cave?" 

Cull:"I believe i mentioned skinning you alive and hanging you by your nerves before eating you?" you could tell he was smiling as he told you.

"S-S-So where do w-we begin" you shuddered.

"I'm going to drown you, so you that you can learn to recover your breath" he said as you fell from shock, "You're drinking water is limited, so do try to make this process short."

End of Flashback

Ever since that moment you've continued to train your breathing. It started with the drowning and you had to learn that skill quickly or else you were gonna die either from the water or by running out of it by accidentally opening your mouth and being forced to swallow.

Cull: tendrils from his hand protrude far enough out to grasp you and pull your head out of the water to which you gasped and gagged trying to regain your breath before the next round.

Y/n:"STOP IT YOU'RE GONNA KILL MEEEE", You coughed out immediately regaining your breath.

Cull:"NONSEnse my boy, you're doing positively spendid! Just look in roughly 6 hOuRS of practice you can hold your BReaTh for up to 2 minutes and your recovery is iMPRoViNg quickly" he complimented. "It gives me hope you'll actually make it out of this wretched hole, besides when the alternative is DeATh, you can't avoid this training." He continued before dunking your head back under the water.