Riku Amami

The protagonist of the story Riku is a highschool student whose lives with his father and stepmother Shizuru. He was in love with Shizurus younger sister Amane but she is presumed dead two years ago in a fire. After sustaining at the start of the series a fatal wound from a Kanshu Neene turns Riku into a special Kanshu that can retain his own consciousness as long as he has a Jinki. His Jinki is given by Youhei and takes the form of a chainsawlike sword with trigger grip. Source: Wikipedia