Doctor Who?

The Demon looked up at Hiroto in contempt, "I won't tell you anything, I… I can't… He's more dangerous than you could ever imagine." The Demon said, with fear present in his eyes.

"Well, he's not here right now, but I am," Hiroto said, before putting some more pressure on the Demon's neck. "Now tell me, is there a way to turn someone from a Demon back into a human?"

"What? That's impossible! You don't think that other Demons have tried before?!" The Demon shouted, with his voice wavering.

"So you're telling me that no Demon has turned back to human before?" Hiroto asked him.

"Of course not! He's always watching, nothing ever escapes that man's eye." The Demon said shivering at the mention of that person.

"Now then, tell me this. Who is he?" Hiroto asked again, with a more commanding tone.

"I… I can't tell you. He'll know." The Demon cried out.

"Muzan Kibutsuji." A female voice sounded from down the alleyway.

Turning his head, Hiroto looked towards the voice and saw a woman in a dark purple kimono with long, dark brown hair in a bun, and large gentle eyes that didn't seem to possess any pupils. A young boy with green hair and light purple eyes, wearing a button-up shirt was accompanying her.

"Who are you? Did you do this?" Hiroto asked with caution.

"The man you were asking of, his name is Muzan Kibutsuji." The woman said.

"No! Tamayo, you traitor! Don't you dare speak his name!" The Demon yelled out.

Hiroto's ears perked up when he heard this. "Did he just call you a traitor? Are you a Demon?" Hiroto asked, before slicing *swish* *splurt* the head of the Demon in front of him off.

"You seem to be more talkative than this one here," Hiroto said as he watched the two people.

"There is no need to be on guard with me. I mean you no harm." The woman said gently.

Hiroto's wariness didn't lessen up, "How can I believe your words?"

"Because we both want the same thing. The death of Muzan Kibutsuji." The woman said with a slight gleam in her pupilless eyes.

Hearing this, Hiroto's guard dropped a bit. "I'll give you a chance to explain yourself."

"Please, follow me." The woman said.

Nodding slightly, Hiroto followed behind the two but kept his hand on his sword hilt just in case they tried to lure him into an ambush. 'I don't want to do this, but this is my best bet for finding answers on Nezuko's cure.'

"If this is a trap you're leading me too, I'll make you regret it," Hiroto said from behind them.

"Tsk, why should we even bring him with us Tamayo-san. He's a Demon Slayer and we are Demons. He might as well just kill us after we tell him what we need."

"It's alright, Yushiro. He won't do that." Tamayo said with confidence.

'Why does she put so much faith in me?' Hiroto thought.

"Tsk, I still don't trust him," Yushiro said.

Hiroto just watched on silently, following them.

Half an hour later, they arrived in the suburbs outside of the city. Walking down an empty secluded street they stop in front of a wall.

"What now?" Hiroto asked, looking around.

Tamayo looked around for a bit before walking through the wall, followed by Yushiro.

"Hurry up, before someone sees us," Yashiro said sticking his head out.

Hiroto, with a hand resting on his katana, followed and walked through the illusion. The moment he stepped in, he could see a big western-style house in the middle of a clearing surrounded by sakura trees. "How?" Hiroto asked.

"A cloaking spell," Tamayo said from in front of the house. She entered and just before Hiroto stepped in, Yashiro whispered to him.

"Don't you do anything to offend her, do you understand? If it was up to me I wouldn't have agreed to let you in our home." Yashiro threatened.

Hiroto looked Yashiro in the eye, shrugging his shoulders. "Whatever you say."

"Hmph," Yashio grunted, before walking into the house. As Hiroto walked in, he noticed that the room was decorated as a doctor's office, with various depictions of anatomy and medicine laying around.

"Welcome," Tamayo said, turning towards Hiroto.

"Before we continue, I would ask for your pledge to never reveal this location to anyone. Although we are Demons, we don't forcefully drink blood from people." Tamayo said, looking at Hiroto.

Thinking for a bit, Hiroto relented and said, "I'll agree. I can see from your eyes you aren't lying to me."

Bowing her head a bit, Tamayo said, "Thank you."

"During your fight with the Demon from earlier, we overhead you asking about how to turn a Demon back into a Human. When we heard this, we realized that you might be different from the other Demon Slayers. Why were you asking him this question?" Tamayo said to Hiroto.

"My family was killed by a Demon, only me, my little brother and little sister survived. But, my little sister was turned into a Demon. So far she hasn't killed any humans yet. We assume she's getting her energy from sleeping, it's been about 2 years since the incident and she hasn't eaten anyone yet." Hiroto recounted.

Both Tamayo and Yoshiro's eyes widen hearing what Hiroto said. "That's impossible. It took me hundreds of years before I could escape from Muzan's grasp and stop my hunger towards humans. Your sister seems to be an anomaly. I assume that and this is just a theory, your sister was turned into a Demon by Muzan."

The moment Hiroto heard this, his eyes started to shake in anger. *crack* gripping his hands as hard as he could out of resentment. "Muzan… was the one who caused all this?" Hiroto spat out.

"That's what I think, yes. However, he is also the most powerful Demon there is. He's the leader and the first one from what I know." Tamayo said.

"Where can I find Muzan?" Hiroto said.

"You can't, not at your level yet. You aren't ready to face Muzan, he's too powerful for you, or anyone in the Demon Slayer Corps for that matter." Tamayo responded.

*Inhale… exhale* Hiroto calmed down his breathing, and cleared his mind. "And what about turning a Demon back into a human? Is it possible?" Hiroto asked.

"... No." Tamayo answered straightforwardly. "Not as of yet. I have been researching different methods to control our bloodlust and need for human blood as much as I could, making some progress but not much. As for a cure, it is very hard to do so. The blood that Muzan puts into a person to turn them into a Demon curses them, making Muzan know whenever someone mentions his name or betrays him."

"I have managed to remove the curse after altering my own body considerably to survive on only a small amount of human blood. But all the blood that we get is donated, none were taken forcefully." She added at the end, seeing Hiroto tense up.

Relaxing, Hiroto then asked. "Then what am I supposed to do? I need to turn my sister back before any irreparable damage is done. Muzan might be the only one that knows how to."

"That may be true, but if I could see your sister, it may give me further insight into how I can turn her back. This would benefit us too, as it may help to turn both of us back into Humans as well." Tamayo said, looking a bit sad.

"Yushiro can get by with even less blood than I would need," Tamayo said.

"How?" Hiroto said, looking at the silent Yushiro.

"I'm the one who turned him into a Demon," Tamayo said.

"You… what?" Hiroto said, surprised by this fact.

"You may be confused since it's generally known that no Demon but Muzan can reproduce Demons. That's more or less accurate." Tamayo continued, "After more than 200 years, I was only able to transform Yushiro into a demon after all."

Hiroto was stunned at what he heard and said anxiously. "You created Demons?"

Tamayo said. "I'd like to make it clear, I'm not trying to create more Demons. I only perform the procedure on the terminally ill or those gravely injured that they don't have long to live. I always ask for their permission beforehand, if they wish to live on, even if it means life as a Demon."

Hiroto stared back into her eyes and thought to himself. 'Her eyes look pure and is absent of any form of deception. She's telling me all of this insincerity.'

*sigh* "Alright, then how am I supposed to turn my sister back? How long do you think it would take?" Hiroto asked.

"I don't know," Tamayo said. "If I were able to see your sister, it would help me a great deal in my research. With your permission of course."

Scratching his head, Hiroto didn't know what to make of all this. "I need some time to digest all of this."

"Certainly, you may rest here from the time being," Tamayo added.

"What?! Ma'am, we didn't agree to this! It was already bad enough letting a Demon Slayer into our home, but to even let him stay here? That's absurd," Yushiro yelled out.

"Yushiro, if you yell out again I will have to punish you. This is my decision to make." Tamayo said towards Yushiro.

"Yes, ma'am." Yushiro responded decisively, thinking, 'She's even beautiful when she's angry!'

"If it wouldn't trouble you, then I'll be in your care," Hiroto said, bowing towards her.

"No problem at all. Although during the day, we won't be out. We'll be resting." Tamayo said, before standing up.

"Now that I think about it, I never asked you for your name," Tamayo said.

"Sorry, I'm Kamado Hiroto." Hiroto said, "Nice to meet you."

"You can call me Tamayo, and he's Yushiro," Tamayo said, gesturing. "Yushiro, please take Hiroto to the guest room."

"Right away, ma'am." Yushiro bowed, before getting up and leading Hiroto to his room.

"Listen, I still don't like or trust you. You better not cause trouble for lady Tamayo. If you do, I'll deal with you myself." Yushiro said, before opening the guest room door.

"Here, your room. The bathroom is to the leftover there. If you need to eat, too bad we're Demons, we don't have normal food, only food for patients." Yushiro said, before walking off.

"Hospitable," Hiroto said, before going into his room and thought over the events from the day. 'I can probably trust Tamayo, she seems to hold a great resentment towards Muzan. I can understand her reason for that anger though, having been turned into a Demon and forced to eat humans to survive. She must have gone through a lot. Wait, just how old is she?' Hiroto thought, before falling asleep in his bed.