Demon King in the Academy

Demon King in the Academy  Upon suddenly transmigrating into the body of the Demon King, the protagonist is seized by panic, knowing the villain's miserable demise at the hands of the hero and his party from The Chronicles of Eldoria: The Hero's Ascendance, the novel he just finished. Realizing he has two months before the original storyline begins, and unable to directly eliminate the hero due to an unseen protector, he devises a cunning plan. He will disguise himself as a handsome boy and enroll in a prestigious hero academy alongside the hero, becoming his most trusted companion. His true goal is to subtly manipulate all eleven beautiful heroines destined for the hero's party, making them fall madly in love with him while maintaining an aloof, "I don't care" facade. He meticulously studies their individual vulnerabilities and desires, using his meta-knowledge of the novel to tailor his approach to each, making them feel uniquely cherished and understood. Through years of strategic guidance and emotional exploitation within the academy, he turns the heroines into his devoted followers, while simultaneously solidifying his indispensable position by the hero's side. In the novel's climactic final arc, as the hero and his party finally breach the Demon King's castle, the protagonist executes his grand betrayal. He backstabs the hero multiple times, revealing his true demonic identity. Given a choice to prove their love, all eleven heroines, completely enthralled by his manipulation, unhesitatingly betray the hero, ensuring the Demon King's complete victory and survival, and rewriting the tragic fate that awaited him.