Tsukihime

The story follows the protagonist, Shiki Tohno, who gained the 'Mystic Eyes of Death Perception,' allowing him to kill anything, due to an accident eight years prior. Frightened by his new ability, he fled the hospital on that day and encountered a mage named Aoko Aozaki, who helped seal the power behind a pair of glasses. For the next eight years, Shiki lived as an adopted child at the Arima branch of the Tohno family. After eight uneventful years, following his father's death, he was summoned back to the main Tohno household by his younger sister, Akiha, who had become the new head of the family. Just as his life underwent a drastic change, Shiki unconsciously used his Mystic Eyes of Death Perception to kill a woman, only for her to appear before him the next day as if nothing had happened.