Toaru Majutsu no Index story
Synopsis
Set in a city of scientifically advanced superhuman  students, but in a world where magic is also real. Touma Kamijou’s  right hand, the Imagine Breaker, will negate all magic, psychic, or  divine powers, but not his own bad luck. One day he finds a young girl  hanging on his balcony railing. She turns out to be a nun from the  Church of England, and her mind has been implanted with the  Index-Librorum-Prohibitorum - all the magical texts the Church has  removed from circulation.