Aa Yuusha, Kimi no Kurushimu Kao ga Mitainda  

ああ勇者、君の苦しむ顔が見たいんだ

My objective is solely to seek revenge against the person who has been mistreating me. I possess the ability to access and explore all of the knowledge available in my mind. Omiya Hoshikuzu, a young man labeled as worthless, discovered the secret to gaining power by studying the books of the world. He then set out to confront his bully, who would later become a hero. The individual who was transferred to another realm with their tormentor will stop at nothing to achieve their goal of revenge.