Energy Hunters Webtoon

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.