October is a time when we consume not just spooky stuff, but also gory, exploitative schlock as well. This is not just true for movies, but for manga as well.
WARRIORS OF TAO (Toma), by Shinya Kuwahara. First published in 2001 and first published in North America in 2004.
PLOT:
For Toma, it was just another day of school (and detention) until he encounters a beautiful naked girl named Itsuki. She's on the run from something called Tao, but before she can explain further she's taken captive by the cruel and calculating Karma and the two of them are transported to the world of Tao. It turns out that the three of them were meant to be part of a force to defend humanity, but Karma sees Toma as only a liability and would prefer him to be removed from the team permanently.
Alone in a strange new world with equally strange new powers, Toma must become a true Warrior of Tao if he wants to survive and save Itsuki.