Energy Hunters

Gu Xinghe is a high school student with few words. After a mysterious bloody red rain, he suddenly found he became the target of a group of monstrous creatures, "the Death Disciples." Whatsmore, his beloved friend Lu Yang fell into a coma on his birthday from the monsters' attack, while Xinghe was saved by a girl with tremendous power. To save his friend, Xinghe joined the "Energy Hunters" academy that the girl attends, and start training to fight the "Death Disciples" and other dark powers.

(Source: Mangatoon)