This was it, Rengoku could see Akaza's fist coming towards his middle. Rengoku accepted that he would die someday, he only felt sorrow at not being there for Senjuro, his father, and the defeat of Muzan. But Rengoku would die protecting the future generations, he would die a great death, and he'd be damned if he didn't make Akaza work for it.

"Akaza!" Came a bellowing cry. The demon froze and began trembling. The yell even caused the slayer to freeze. Akaza jerked away, taking five steps back and lowering his hands to his side, his head also twisted viciously towards the tree line.

Rengoku followed the demon's line of sight. Seeing a beautiful woman power walking towards them. A beautiful white western-style dress adorning her figure. It was flowing in the breeze and was enchanting, dazzling, just absolutely exquisite, the woman could also be explained using those words. Rengoku felt a flush brighten his cheeks at seeing you speeding towards them. Who were you? And how did you know Akaza?

"Mother!" Akaza cried in embarrassment. Mother? Rengoku twisted his head back towards the male. Rengoku was flitting his gaze back and forth between the two of you. What is going on here? He found his own sword lowering to his side. Akaza seemed petrified of the woman, and as she got closer Rengoku understood.

As you got closer Rengoku's own body began to tremble. You were far more powerful than you looked, it sent every one of Rengoku's nerves on fire. He needed to run, he needed to flee. He tried to stop the trembling, desperately, but he couldn't seem to steady his hand.

You made it much closer and were now glaring at the demon, "Akaza, we've talked about this," you took an exasperated tone, hands resting on your hips. The posture you took accentuated your body even better for Rengoku to see, and he was doing his best not to choke. "But mother," whined the demon.

"No," you all but growled, "we've discussed this. We agreed. I want to hear absolutely none of your excuses right now. We're going to have to have quite the talk once I smooth this over. Do you understand?" You had crossed your arms at his point. And Rengoku couldn't help but choke. Your eyes flitted over towards the slayer. You stepped in front of Akaza, his eyes just barely peaking over your head. "Get off your tip toes Akaza," you said not even looking back at the man.

Akaza pouted but did as you said, no longer being able to see the slayer over your head. Akaza looked like a child that had been scolded, which he technically was but this was all so incredibly difficult for Rengoku to wrap his head around.

"I'm so sorry about his behavior. We agreed that he wouldn't go around killing anyone but," you turned your head to glare at the demon, "someone couldn't help themselves."

"But mother," Akaza pouted and managed to get close enough to you to wrap his arms around you, his chest resting against your back. He rested his head on your shoulder, and proceeded with his pout, whine, and stomping his feet routine. "I don't wanna hear it you brat," you gripped his face in your hand, glaring at the demon. "You broke a promise, and I do not tolerate that sort of behavior. You're lucky I'm not punishing you right here in front of these people." Yep, color Rengoku confused as to what the relationship between the two of you was. You turned back towards the slayer, "I'm so sorry for his behavior. And I am deeply remorseful about any injuries or damages Akaza may have caused. I hope there is some way we can help."

Rengoku could only stare at you. Sense finally invaded him again, "Demons don't have parents. They are all created by Muzan," Rengoku spoke as he raised his sword again. "Correct you are young slayer. While I am an exception, Akaza here isn't. But he's working for me, at least he's supposed to be." You glowered. Akaza whined again, tightening his hold around you.

"Many of Muzan's demons call me mother because I love, care, and cherish each one, whether I am able to save them or not." You turned towards the younger slayer, "Tamayo has spoken of you Tanjiro, it is lovely to finally meet such a wonderful," you glared at Akaza again, "and well-behaved boy."

Tanjiro sat surprised, "you know lady Tamayo?"

"Of course I do silly. I am also her mother," you giggled, covering your mouth in an attempt to control your laughter. "She spoke fondly of you, and I am happy that you seem to live up to her praise." Tanjiro smiled brightly towards you, "does that mean you are the great lady (Y/n)?"

"Oh my goodness, I haven't been called that in so long," you blushed, holding your warming cheeks, " But you are correct dear, that is who I am." Tanjiro smile only seemed to brighten, "then it is lovely to meet you Lady (Y/n)." Akaza was grumbling at your side, holding tightly onto you in a hug.

This is my only chance to catch her by surprise, it's my only hope. I can't let her get to Tanjiro, or anyone else. Rengoku thought, completely oblivious to the conversation that was being had, and launched himself at you. Akaza seemed to have caught the movement, however, unlatching himself from you and stepping in Rengoku's way. "Don't touch mother," the demon hissed as he grabbed the slayer's sword, blood running down his arm and dripping off his elbow.

You slowly turned back towards the older slayer. "Oh Akaza, it's not that serious. Why don't you step back. I can't have you hurting the Flame Hashira now can I?" You gave the pair a closed-eye smile with your hands clasped in front of you.

Akaza grumbled but jumped back nonetheless. Rengoku could handle Akaza later, he seemed to listen to you, so you were a bigger threat at that very moment. Rengoku launched back at you, "Third form, Blazing Universe!" Rengoku cried, putting in as much effort into his downward stroke. "Hm, cute," you whispered in his left ear.

Rengoku took a quick side step, slashing up and to the side. But this time he heard your laughter in front of him. He tried to use different forms, slashing in all directions, and trying to follow your movements.

You were suddenly beside Akaza, "I see now why you were here Akaza, he is quite fun." Akaza sent you a hopeful gaze, "but no you are still in trouble because you were about to kill him before I intervened." Akaza went back to pouting towards the ground and kicking his feet in a guilty manner.

"Why don't you stop Rengoku, I don't want you to hurt yourself anymore by proceeding to irritate your injuries in such a way," you smiled at the slayer who was panting. You were too fast. If you were anywhere near the level of Muzan the slayers were royally fucked.

But Rengoku would never quit, he would fight until his dying breath. "I can't let you leave, I must end you both for the safety of the world. Demon's, no matter who must all perish." You frowned a sad frown, like a mother whose child just scraped their knee. "Rengoku dear. That kind of thinking will get you killed far sooner than any of us would like." Rengoku almost went weak in the knees at you calling him such a lovely pet name.

"I will never quit!"

"Well then, I guess I have no choice," you mumbled sadly. "Mother?" Akaza questioned as he gripped your wrist. "Don't worry honey, I won't hurt him," you grinned, grabbing his face and bringing it down to peck his forehead. Akaza nodded, smiling softly at you.

You walked towards the Hashira, biting the tip of your thumb, running the bloody area down one arm, and rubbing a circle into your palm. A bō staff appeared in your grip. Rengoku was absolutely fucked, and he knew that.

You both launched yourself at the other, your blood staff being able to withstand each blow from Rengoku's sword. Any strike you landed hurt, but didn't leave any visible mark. You were fighting him with a staff, while you could have easily killed him by now. You were a terrifyingly powerful demon, and yet he and everyone else were, still alive.

He was desperate to land a hit, and in his desperation, he left himself open. You smirked, closing in on him. You were chest to chest, an absolutely devilish smile adorning your face. "Boop," you commented teasingly, a snicker following at his shocked face. You had in fact booped his nose. Rengoku found himself stuttering, stumbling backward.

You giggled, twirling your staff and having it dissipate from your grasp. "Well Rengoku, it's been a delight but I think it's about time for us to leave," you turned towards Tanjiro, "and I have a feeling we'll be seeing each other soon." You winked towards the boy, turning back towards the Hashira. "And you, good sir, I dearly hope to see you again," you blew a kiss, grabbed Akaza's hand, and seemed to fizzle out of existence.

Rengoku fell to his knees after you both disappeared. He was using his sword to keep him up, trying to regain his breath. "Rengoku!" Tanjiro called out, stumbling towards the older slayer. Rengoku was gasping, his whole body being racked with shivers. "Tan-Tanjiro, who was she?" The Hashira gasped out desperately.

"That was Lady (Y/n), she's an old but powerful demon, but Lady Tamayo trusts her so I do too," Tanjiro said, nodding his head in affirmation. Rengoku looked at the young slayer, "I could be dead Tanjiro, why aren't I?"

"Lady (Y/n) doesn't need to eat humans, and anyone who drinks her blood doesn't need to either. From what I know she's as old as Muzan, they were born at the same time, and in the past hundred or so years she's been fighting against him. Apparently she only 'recently' awoke. She's been in what other demons call hibernation for a really long time."

Rengoku still couldn't prevent his whole body from shaking. "So she's as old as Muzan?"

"From what Lady Tamayo told me, yes. But she's only recently been around to fight against him. Apparently, she has a way with bringing the human out in Demons," Tanjiro shrugged, it seemed like a fun little story to tell Nezuko when he first heard it, but now that he had met you he feels he should have listened a bit closer.

"Kamaboko Gonpachiro!" Came a deep cry, the boar-headed boy came running from the train wreck. "Tanjiro!" Inosuke and Zenitsu came running towards both slayers. They tackled the younger slayer quickly, Nezuko rushing out not long after. They cried while hugging him, "we thought you both died," Zenitsu cried.

Tanjiro couldn't help but laugh. "It was scary but a very nice woman helped us." Zenitsu froze, "woman? Tanjiro were keeping a beautiful lady from me!? How dare you!" Zenitsu whined and lightly punched the other slayer repeatedly. "I think she was more interested in Rengoku, Zenitsu."

Zenitsu turned towards the Hashira, who had gained his breath and remained crouched due to the injuries Akaza was able to deal him. "Pft, as if. Who was she?" Zenitsu was far more interested in you than how anyone else was doing.

"She's a demon," the hashira breathed. "She's a what?" Zenitsu couldn't help but laugh. There was no way Rengoku had just said a demon helped. "She is a demon," Rengoku confirmed. Zenitsu froze. "She was a what!" Came the shrieking cry. "You faced two upper moon demons!"

Tanjiro cringed at the volume, "no, just one. Akaza. He's the upper moon three. Lady (Y/n) is different. She's not allied with Muzan." Zenitsu nervously laughed, before seeming to pass out. Tanjiro and Inosuke shrugged. "So Gonpachiro, how strong were they? I bet I could have beaten them." Inosuke boasted.

"You would have been killed," Rengoku said sternly. "She could have killed me, but she didn't. I don't know why." Rengoku mumbled, feeling extremely puzzled by your actions. "She even stopped the upper moon three from killing me. I don't understand it at all."

- - - - - - -

The Kakushi showed up not long after, helping deliver first aid to any civilians and the slayers. Nezuko was in her box, a Kakushi holding it, and another holding Tanjiro. They were all alive, thankfully. Had you not been there it would have been a devastating day for the Demon Slayers.