Sharp Edge

is a Japanese light novel series written by Shinichi Sakairi, with illustrations by Nagi. The series began publication on April 10, 2003 by ASCII Media Works under their Dengeki Bunko publishing imprint.

Synopsis
Kaname was picked up by Heinz, a sweeper, who was lonely in heaven. Heinz slammed his "killing" technique into Kaname, and she responded. The days of training earnestly grow Kaname into a resolute girl. At that time, her parent, Heinz, is killed. Her opponent was a sweeper with peculiar abilities, "Witch" Sylvia. Moreover, behind her is a family that divides the city. Heinz's presence wasn't light for Kaname to simply say that her opponent was bad. In the overwhelming disadvantage, Kaname decides to defeat Sylvia- !?