Reader POV, present day

I made sure my face was hidden under my demon mask, my staff gleaming menacingly in the moonlight.

"Who are you?" I demanded.

The three boys jolted and I immediately saw the one with blue eyes moving his hand down to his sword and I cut it in half with my blade, glaring.

"So you're demon slayers, eh?" I taunted. "You aren't welcome here."

As I moved closer, my body froze when I saw what the younger boy was wearing.

Is that...

I lowered my blade and reached out to him, my eyes wide. "Young man. Where did you get those?"

The boy looked so confused. "My family's had these for generations."

I looked closer at him, going closer to the fire they made and I gasped.

"Yoriichi?"

"Eh?"

The boy with blueish eyes took a look at me. "Yoriichi is dead."

I gave him a sharp look and my eyes started to glow as the stars appeared. "I know that, young man."

"Hey! You're not much older than me!"

I looked around and no one else was there so I slowly took off my mask and put it in the small bag I had hanging off my obi.

"You must be a descendant. Now that I think about it, all four of you are my descendants."

The boy whose sword I cut stood rigid. "How could I be related to them?"

I looked around and beckoned them to follow me. "Come. It would be unwise to lurk here any longer."

They followed me and I placed a special seal against a rock and turned it, the rock groaning and revealing a staircase.

"Why should we follow you-"

"Because I'm exactly who you're looking for. The Star Guardian."

The group stared at me like dumbfounded ducklings but I ignored their questions.

The rock moved back in place as I lit the torch, the water trickling down the rocks.

"We must move quickly."

I sensed the demon inside the smaller boy's box knew what exactly I was but I didn't bother to say anything.

The lights all around the village moved around the bushes as we entered, the three boys filled with fatigue from climbing multiple steps.

"Who are they?" I heard the other people and demons say.

I carried the flame to the center and put it in an oil basin. "These four...they are the descendants of my three sons. But what differentiates them from you is the fact that they arrived during the Blood Moon festival. A sacred festival. Long ago, I was given a vision of them. The time has begun."

As the flames roared, my other descendants and followers began to chant and look more hopeful.

I pointed to the blood-red moon. "The time of Muzan's downfall is upon us after all this time."

TANJIRO POV

We watched with curiosity as the people of the Starlight Temple danced and shared food that was delicious.

The Star Guardian who insisted we call her Lady (y/n) was sitting next to Nezuko, speaking to her in a gentle voice and then nodding.

"Gale," Lady (y/n) called out. "Please bring the blue spider lily tea."

"The blue spider lily?" Tokito's eyes widened. "That's Muzan's missing weapon. He wants to use it to conquer the sun."

Lady (y/n) sadly nodded. "We have kept it safe here. This is the only place in Japan that has them. My temple protects it and we use it for good."

A little demon boy returned and the demon lady poured a cup of purple liquid in a cup, handing it to Nezuko after gently removing her bamboo stick.

"Drink this," she said kindly. "You will never have to fear the sun again, my dear."

Nezuko did as she was told and shrank, curling up next to our ancestor who patted her head affectionately.

"So how are we your descendants?" Kiyoshi asked. "I mean, doesn't that seem sort of weird?"

The pretty demon glanced at all of them before going back to petting Nezuko.

"I'm sure you know that you are a descendant of my dear son Yoriichi," I told Tanjiro. "And Gojo Kiyoshi is the descendant of my youngest son Soma."

"But what about me?" Tokito frowned. "How am I related to them-or you?"

Lady (y/n) took out a bamboo flute from her side. "Through my oldest son Michikatsu." Her eyes grew sad. "Our family history is quite complicated. Not only are you related to me, but you are also a descendant of the demon king himself. Except you, Kiyoshi."

"I know," Tokito mumbled. "It's a dark history that Ubuyashiki chooses to hide from the rest of the corps."

Lady (y/n) glanced up at the sky, taking a deep breath. "I would imagine so. Over the generations, I've watched all of your ancestors -my descendants grow and cultivated their art. It's a shame that sun breathing hasn't been used in centuries but..." she paused before shaking her head.

"It's best if you find out yourself. For now, get some rest. We will have guards stationed."

The pretty lady stood up and beckoned us to follow her, explaining each one of us would be allowed to sleep in a nice area.

"I understand you have come to ask for my help in battling Muzan," Lady (y/n) frowned. "I cannot promise you that I will be able to hold him back as he has grown even stronger than when I last saw him a hundred years ago."

"We understand," Tokito said with a newfound respect for our ancestor.

"Good. Get to sleep, little demon slayers. Tomorrow will bring a new challenge."

Unfortunately for me, I wasn't able to sleep. Tiptoeing in the night, I found her sitting outside underneath the stars, staring up and humming.

"Excuse me?"

She jumped and turned her head. "Yes, Tanjiro?"

"Can you tell me if my sister and I are the keys to stopping Muzan? Master said-"

"I don't care what he said. Anyone had an equal opportunity to strike Muzan down. It is a matter of believing you can," she said. "When I faced him centuries ago to fight for humanity, I was only able to fend him because I have a starlight demon slaying technique."

"But my son. Oh, my son." Lady (y/n) looked up at the moon, slight tears forming in her eyes. "He was so brave. He almost struck Muzan down then almost struck down his brother. It was his ultimate sacrifice that bought humanity a couple more centuries."

"I was only alerted of their battle after it began and my son...I only caught a glimpse of Michikatsu as he fled. I held my dear Yoriichi tightly." Lady (y/n) looked down at her shaking hands. "His very last words to me: "Mother...is that you? I guess I really am going to Heaven. Please don't cry. I've lived a long and happy life. You look just as beautiful as I remember you." 

"Then he died. He died with a smile on his face. My son.  He was truly God's gift to me and humanity. Even though I had turned into a demon, he never once tried to kill me. His noble spirit has passed down to generations of our family, Tanjiro. You bear the weight of a heavy legacy on you." She reached out and gently held my face, placing her forehead on mine.

"As your ancestor, I am exceedingly proud of the strength you carry on. To lose one's family is tragic and you stayed strong for your sister. You are truly the pride of all of those who walked before you. I have thought it over. The reason you came was to get my help for taking down Muzan. I will help you."