[WP] a story in which the protagonist (and reader) doesn't realize until the end that they are the "bad guy"

At last, this was my moment to shine. The love of my life had been kidnapped. Held and imprisoned inside a castle. She had temporarily escaped the monster guarding the castle to show me the image of the monster. I couldn't believe my eyes. Not too long ago, she had rejected me. Realizing that this was my chance to show my love and dedication to her, I graciously accepted the task of avenging her and ridding the world of this monster once and for all. It was at this moment that I realized to my utter horror that the monster had brainwashed her. This ugly... THING had tricked her and beguiled his way into her heart. Anguish filled my heart and I gripped my sword tightly. Unforgivable. It was with my heart full of woe that I was forced to leave her in town. She might have gone to warn the monster of my plans, if I hadn't.

As I rallied the village to aide me in the siege of the castle, I turned my anguish and anger into the fires that fueled each of their spirits. When I finished, I stared at them and received the full might of the righteous anger that was so appropriate for such a despicable foe.

It was over for me, I had made a mistake in the fight. Perhaps I should have tried to kill him quicker, before he had overpowered me. Oh well, it seems over now. My feet are dangling over the void. The monster choking me, holding me so I won't fall. I stared in horror as he brought my closer and closer to its mouth. I thought he might eat me, but no. He placed me beside him and said "Get out." I couldn't believe it, he spared me. I choked and gasped for air while he lumbered away. As I was just recovering, I heard her voice. The voice of my love calling for the monster. I looked up as a shiver ran down my spine. The beast was reaching for her. Blinded by fear and terrified at the thought of my love being taken in by this thing again, I lunged forward and drove my knife deep into the side of the monster. It was not fatal, not yet. I pulled it back out and slipped. The blood of the creature had wet the floor beneath my feet. I fell backwards and reached my hand out in desperation towards my love. Both me and the creature were falling ever so slowly and I watched as she grabbed the arm thrown out by the monster. I fell backwards towards the void and my last thought ran through my head. "Maybe she did love him. Maybe Belle really did love the Beast."

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