Clean Hands is an achievement/trophy in Dishonored. It is unlocked by finishing the game (excluding the prologue) without killing anyone.
A tweet from Arkane developer Harvey Smith confirms that wolfhounds, rats, Fish and river krusts do not count toward body total and therefore will not lock the achievement if killed.
Trivia
- Although not counted as a mission, killing the Weepers below The Hound Pits Pub for Havelock before the mission House of Pleasure will also count against the Clean Hands achievement. However, it won't count against the Shadow achievement.