Demon Slayer: Tomioka Giyu X You [Platycodon Flower]

The bounty hunter (you) accepts an order to kill the swordsman Tomioka Giyuu for your dream, and pretends to love him for this purpose. Three months later, you were really moved by him. To protect him, you lied that you had "never loved me" and traded serious injuries for the termination of the mission... Pure love, otome-oriented, including self-set imaginary world line, OOC apology