Sergeant! Reader x rengoku

y/n is coming back from the military after 10 years you were honorably discharged Due to a serious injury you thought it was minor due to all the injuries and surgeries you went through (leaving horrible scars on your body) but to they thought different. you come home and find your family dead there's 6 graves beside the house two graves are missing knowing this you know two of your siblings are alive you weren't sure if you were ever going to find them again you get told that your family was killed by demons and that your brother went to go train to be a demon slayer so you did too you know that your brother is alive but who else is?.. once you find your siblings you also meet a certain flame haired hashira

(Smut Chapters will have "🍋")

Warnings
Suicide & suicidal thoughts (only In the beginning!)
bullying
sexism
S3xu@l harassment
Child abuse
Drug abuse