Watashi no Messiah-sama

Shinya doesn't get good grades. He's weak, a coward, not athletic… he's a general good for nothing. One day; however, he meets Haruna, a girl who could change his life forever. Haruna tells Shinya that he is the Messiah, the lord chosen to save her world, and that she is his shield.
Can it be true? Is Shinya's life of ineptitude balance for this one grand cause? Is he the Messiah? If he is, can he save himself let alone an entire world?

Originally ran as "Watashi no Messiah-sama" (26 chapters) and "Watashi no Messiah-sama ~lacrima~" (35 chapters)