Kimetsu no Yaiba/Demon Slayer Isekai. Female lead.

Stronger

Haku sat in front of Kagaya sipping tea. He had summoned her to discuss the remaining upper moons and the inevitable upcoming battle. Haku had avoided the topic of Akaza so far, but she knew that was far from avoidable. Kagaya finally broached the topic. "So Kyojuro tells me that upper moon 3 visited you and short of pledged loyalty to you." Haku nodded and sat down her cup. "Yes. I used my blood to free him from Muzan. I never told you the story of how each became a demon, but that is part of my knowledge. Akaza was a very kind man named Hakuji in the past. He was set to marry the daughter of a famous martial artist and inherit his dojo when an opposing dojo poisoned their well in spite and greed killing his fiance and her father. He lost it and killed everyone in the other dojo with his bare hands. Muzan came thinking a demon was running amuck but instead found Hakuji. He attacked Muzan who easily defeated him. Hakuji did not care about anything anymore so Muzan turned him. He lost his memory and was named Akaza." Kagaya sat thinking a moment. "I will leave it to your judgment, Haku-san. There are demons among us that are not against us." Haku smiled knowing he was talking about Tamayo. "I hope Tamayo has made plenty of cures. I gave her more blood, and I think I know how to weaponize it myself now. Injecting Muzan and the upper moon's with the cure should help in defeating them. I honestly doubt any of them would concede to becoming human again. Even Akaza...." She trailed off, unsure if the demon would be able to live with himself if he regained his memory and returned to being human. He had killed his fair share of humans, which was not something his human side would do needlessly. The thought of him meeting his end by his own hand as he had in the original made her stomach churn. Kagaya noticed her sudden melancholy and placed a hand on her shoulder. "Sometimes fate cannot be changed child. Though you have changed so much already, some things will be as they are." Haku gave a small smile to Kagaya then stood up and bowed. "I'll take my leave now Kagaya-san. I need to stop by the butterfly mansion." Kagaya nodded and waved goodbye.

Haku made her way to the butterfly mansion where Tamayo was staying with Shinobu, working on making cures and poisons from Haku's blood. The cure had been a success and cured Nezuko, though the young girl was in a coma. Shinobu and Tamayo were both sure she would wake in time. Haku waved at the two as she entered the darkened room. Candles provided the only light. Tamayo had not taken a cure to become human, and Haku wondered if she was still set on sacrifice. She would not stop her. Tamayo had lived a long time and knew what she wanted, but Haku hoped she would become human and live the rest of her life with Yushiro. Yushiro remained a demon as well, refusing to change unless Tamayo did. His blood demon art would be helpful for what was to come anyway. "Hey guys. Doing well." Shinobu turned with her usual smile. "Oh yes. We have not been able to get quite as many cures as we would like. It takes quite a bit of blood from you and the calculations have to be exact or it could end up having the opposite effect and strengthening our enemy instead." Haku sat down and rolled up her sleeve for Tamayo. "Alright then. Thanks Haku-san." Haku smiled. "No problem. I want to help as many as we can and I want to beat Muzan. I don't want anyone sacrificing themselves to be able to beat him or one of the remaining upper moons." She cut her eyes at Shinobu who's smile faded for a moment then returned to normal. "Oyakata-sama told us not to pry, but I really do wonder how you know these things." Shinobu gave her reply and returned to her work. Tamayo paused her work a moment and returned to taking Haku's blood. "Yes, some of us have given up in the overall for one reason or another." Haku felt tears prick at her eyes. "I think everyone should live to see a world without Muzan. To see a world without demons who hunt and kill. Besides, demons will still exist with Muzan gone until we cure or kill those still around Japan. It may take a while, and we need those who can fight to live. Live and see those who came after surpass them. That won't happen if we all die." Both Shinobu and Tamayo listened intently, eyes slightly wide. They exchanged glances and smiled. A new fire for life was in both of them. When tamayo finished Haku was feeling a little drained, but she brushed it off. She wanted to get back to the Rengoku estate.

Haku looked up at the sky. Stars were becoming visible as day gave way to night. She quickened her pace. She was already running behind expected schedule and she was sure Kyojuro would be worried. She was paying little attention to her feet, and combined with her blood loss were a dangerous combination that resulted in her falling forwards heading straight to a face plant. She flt an arm wrap around her waist and stop her from falling. The arm around her belonged to Akaza who looked at her disapprovingly. "You should be more alert. Muzan still has eyes on you." he pointed into the brush where a demon lay dead. Akaza had saved her without her knowing. Haku steadied herself back into standing. Akaza kept his arm around her. "Sorry Akaza. Lost in thought I guess. How do you feel since ditching Muzan?" Akaza thought for a moment. "Different. Not just the lack of his presence. I feel....stronger than before." Haku held her hands in the sign for ram. "Allright, let me check it out. Inyo breathing: sixth form: Onmyoji's Divination." She reached out with her senses to assess Akaza's power. She staggered, thankfully not falling since Akaza still held onto her. "You're probably stronger than Doma now! At least as strong!" Akaza had a cocky grin and Haku could not help but laugh. He would love to stomp Douma, and Haku would love to as well. Akaza seemed a little embarrassed that Haku had practically read his mind and pushed Haku forwards. "If you can laugh, start walking!" Haku continued to laugh, but walked with Akaza side by side until the Rengoku estate was in sight. He turned to Haku and brushed her hair away from her forehead and placed a soft kiss. He then vanished. Haku was left a blushing mess. The door of the estate opened and Kyojuro stood, obviously ready to go hunting for her. "Oh! Good! You're back safely! Come I have exciting news!"