Note the reader is 8 years old in the prologue.
In a village there's a samurai who fell in loved with a demon slayer, they both had a child together and they lived a happy life but that doesn't last until a horrible massacre happened one night.
A young boy was training using a wooden sword and he hits the dummy a million times until he heard a chuckles, the boy turned and saw his brother.
"Nice hits but you could used some more balance" he said. As he help the younger sibling with his stance."now make sure you keep a close eye on your opponent take deep breaths and be patient."
The younger nodded and took a deep breath as he strike at the dummy again.
"Good, you manage to keep your balance and learned to be patient".said the older.
"Nii-Chan why be patient shouldn't we be quick while fighting" the younger question.
"Well yes but in some situations you must be patient and wait for the right time to strike, the most important thing in fighting is that you must save some of your energy if not you'll get exhausted and the enemy might take that as an advantage" the older explain.
"I can see why father was never tire when you trained with him, you were ways losing to him cause your tired".said the younger.
The older laugh and rub the back of his neck.
"My, my are those two my young warriors"
The two boys looked up and saw their mother.
"Okasan!" Said the brothers.
"I see your brother has become a fine teacher"the mother complimented.
"I'm not as that good of a teacher like father"said the older.
"Of course you are my son" another voice came and they see an samurai at their door way.
"Father!" The two boys ran to him and hug him.
"Your back! Wait how was your mission and How long are you gonna stay here?"the older question.
"Don't worry my son I'm only be here for the week now I want to spend time with my family".said the father a he patted the two boys head. "Satoshi, (Y/n ) my young warriors".
The two boys smiled.
Later that night the four family members were in (y/n) room.
"Time for bed (Y/n)" said Yuki.
"Aww do I have too" whine the young one.
"Well fo you want the demons to come get you".Satoshi joke.
"Demons are not real are they?". (Y/n) ask.
Yuki and Satoshi looked at each other.
"Well little do you know there are other warriors out there fighting them". Yuki said sitting next to her younger son.
"Warriors like father?". (Y/n) question.
"yes like your father but when your father fought in the day these warriors fought in the night, there called the demon slayers". Yuki replied.
"Demon slayers?". (Y/n) question in curiosity.
"Yes demon slayers are warriors that fight in the night to keep people safe from the clutches of the demons". Yuki continued."It's there job to stop the demons for creating evil on our land and bring peace into the world".
"Whoa, being a demon slayers sounds amazing".(Y/n) said.
Satoshi chuckled.
"They are aren't they, but I must go now". Said Satoshi.
"Wha!? You had to go Onii-chan?". Said (Y/n).
Satoshi nodded.
"Yes I have a mission to get to from my master so I won't be back till morning". Satoshi replied as he left the room.
Yuki tuck (Y/n) in his funton and kissed his head.
"Good night my little one". She said as she left the room also.
Now it's just Fujii and (Y/n), Fujii sat down beside his son and rub his head.
"Father can I ask you something?". Fujii looked down at his son.
"What is it?". He ask.
"Why does brother always go out at night does that mean demons are real".(Y/n) ask looking up at the ceiling.
Fujii pause for a second and then said.
"Well that's the main point of being a samurai we sometimes go out at night to protect people from bad people, like the demon slayers your mother mentioned earlier". Fujii explained.
"Oh okay, do you think someday I'll become a samurai like you someday".(y/n) ask once more.
Fujii smiled.
"I'm sure you will, someday you'll be able to be the greatest samurai in our families generations". Fujii kissed his son head and got up to walked out the room."Good night my son". He closed the door close and (y/n) got up and went to his window looking up at the moon and stars.
"Don't worry father I won't disappoint you I'll make sure to make you proud".(Y/n) said to himself.
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Few hours later.
Fujii was up late written in his journal until he heard a someone barge in from outside, waking up his wife, they both ran outside to see their son in a terrible state, he had scratches and cuts everywhere, he fell to the ground.
"Satoshi!" Yuki ran to her son."Satoshi what happened!?".
"O.....Okasan........"
Fujii rant to his son.
"Who did this to you?".he ask.
"Oi, oi, what do we have here".
The three looked up to see three demons one with pink hair, one with fans and one with 6 eyes.
"Yuki take Satoshi inside now". Fujii tell his wife.
"Fujii-san~ it's been so long since I've last seen you I've missed you so much" the demon with the fans said.
Fujii growled.
"Oh~ so stubborn as usual, such a shame since you're married to this women but oh well". The fan demon said.
"What do you want you demons". Yuki growled.
"Oh miss Yuki just for two things we want for our meal you and your son, since he wants your husband alived". The fan demon smirked.
Yuki growled.
All sudden the pinked hair demon went to grab Fujiis face but not until Satoshi slice his arm off.
"Don't touch my father" said Satoshi.
"Not bad but let's see how strong you are boy". Said the pink hair demon.
The pink haired demon and Satoshi went against each other despite that Satoshi is injured he can still fight if he wants too.
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(In (Y/n) room).
(Y/n) woke up hearing some noise of fighting outside, he was afraid so he hid under the covers until he heard his door open, he pull down his covers and see his father all dirty, and had some parts of blood on his clothing and he walked towards (Y/n) and picked him up and ran out the estate.
"Father what's going on where's Okasan?".(y/n) ask.
Fujii didn't say anything and ran away from the estate as far as he can.
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In the morning Fujii and (y/n) made their way to another estate, and knock on the door, the door opens and sees a man wearing a light blue yukata.
"Fujii-san? What are you doing here what happened?". The man ask.
"Kusunoki, iI'll explained everything but I need get (y/n) inside for him to sleep he hadn't slept since what Happened". Said Fujii.
Kusunoki nodded and let Fujii inside the estate.
"Lay him on my funton and the come to the living room so we can talked". Fujii nodded and lay his son on the Funton.
_________________________________________
Few minutes later.
"I can't believe they Oh god" Kusunoki looked down in sorrow.
"Kusunoki I must as you a favor".Fujii ask.
"Yes?".
"Please take care of my son (Y/n), train him to become a demon slayer".Fujii said.
Kusunoki eyes widen.
"But what are you gonna do?".Kusunoki ask.
Fujii sigh.
"I must leave this place and make sure that I'm far away from you and (Y/n) cause seems like he's after me if he finds out I'm here with you two he might kill you both". He replied.
Kusunoki sigh and nodded.
"I understand but before you go make sure you say your good bye to him" he said to Fujii.
Fujii nodded and walked to the room where (Y/n) is and asat down next to him putting a hand on his shoulder.
"(Y/n) wake up" he said softly.
(Y/n) woke up still tried at his father and stood up.
"(Y/n) listen to me carefully, your father has to go for and for everything I've done to protect you no matter how things change never lose who you are be yourself" Fujii Hug his son with tears in his eye "Good bye my son some day we will meet each other again in the future thats a promised".
(Y/n) hug his father back sobbing until he fell asleep once again from his tiredness.
Until then a few hours later Fujiiwas gone and. Kusunoki told him he's going to train (y/n) under his wing and become a demon slayer to avenge his family.
To be continued.