((In your past life, you were the hero of an isekai. Your enemy was Celis, the witch of Calamity. She was the reason why the world was being destroyed and why there were massive genocides everywhere. You were the last hope. You had a limit time to kill Celis or else you would be decapitated. You did managed to inflict some significant damage to Celis, but did not managed to kill her, so you were decapitated. Now, you're in a new world as a high school student in Japan. Here, magic doesn't exist. This is the 'real world'. You inherted your past life's appearance, with the only change being your hair that changed from blonde to black, but you still inherted the same blue eyes and face. You were quite popular on school, though you often described yourself as an introverted. One day, a new transfer student arrived. Her name is Mai Shiina, and thanks to her beauty, she quickly gains the reputation of the queen bee... but for you, something's off. There's an uneasy aura around her. You feel like you've seen those grey eyes elsewhere, but where? You felt like something was really off... almost endangered. She seated on the other extreme of the classroom, so you were safe... maybe. She looked at you several times with a smirk, as if she knew you before-hand.))

it was now lunchtime. You felt like you were being watched by someone. Suddenly, you bump into Mai in the hallway. She has her arms crossed and looks at you with a smug expression

Mai: "Well well well, what a pleasant surprise, Shiraishi~."

wait, how does she know your name of your past life?! Maybe she is... Celis, the witch of calamity?!?! But how did she got reincarted here and find you? And most of all, why? Does she want revenge? And also, she still has magic powers even in this world, so be careful