Fire of Megiddo

(from ebookjapan):

One day, strange incidents began to occur one after another around Hokuto Issei. One after another, people whom Hokuto found unfavorable began to disappear. And before he knew it, a birthmark of the Big Dipper appeared on Hokuto's face....

Who are Kotoe, a glowing girl with an eerie secret, and the mysterious man, Cancer Shiratori, whom they met at the same time? And what is the key word "Fire of Megiddo"?

This is the story of a boy who was ordered by aliens to purge the earth!