Guren Five, Tome 1

"Enter a world of sci-fi and action-packed battles as high school delinquents are recruited to fight against an alien horde. Follow Harmony, a girl from space, as she tracks down the supposed "strongest warriors on Earth" at Kyuren High School. But will these troublemakers be enough to take on the deadly Gears and save the universe? With stunning character design by Yuki Kodama, this manga combines the best of both genres for an epic adventure."