How did I get here again...? [Muichiro Fem!Reader x Mha]

~Prologue~

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The screams of a creature, no, a young male, could be heard, but we're shortly followed by a slash of a blade. A monster dissolving into nothingness and the slayer standing beside it became the only evidence that there had been a problem to solve from the start.
"Thank you,... huh?" The boy said after a few seconds of taking in his current situation, but where did his hero go?

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As the famous hashira, the mist hashira, also known as (Y/N) Tokito sprinted through the serene forest situated near a secluded village, a new feeling settled in the air. You stopped, realising that something was off. Was it a demon? You couldn't smell any blood or necessarily alarming scents. Was it a wild animal? No noises were heard, other than your own breathing. You began to walk. Did you mean to? No. It was as if the mist that loomed around you was guiding you to a,... mansion?

You looked up to meet a tall estate, most likely abandoned. The cob-webs that hung above on many of the average sized windows and the weak wooden door that barely hung on its hinges were evidence of its loneliness. Your feet were carried in through the door, but a light, yet heavy feeling washed over you, as if the mist itself was taking over your body and in an instance, you gave way,...

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