The Empty Box and Zeroth Maria, Vol. 1 (light novel)

Kazuki Hoshino treasures nothing more than his ordinary life, and March 2 should have been an ordinary day. The arrival of a transfer student, the mysterious Aya Otonashi, shouldn't have shattered the world he knows. He's never seen this girl before in his life, but she says she's met him thousands of times--and declares war on him for a crime he can't even remember... As the truth begins to unravel, nothing is as it seems, and at the heart of it all is a wish powerful enough to change ever...