Reaper, a definition given to those who qualify based on neutrality within certain situations, means to take the souls of those who have already died physically. A specialized Reaper would have to be neutral in case of unwilling spirits. A Reaper would transcend to the "Groundlayer", or Earth as it is called by humans, and find wandering souls to send back to the Underworld and their afterlives. The scythe of the Reaper is a weapon used to reap evil souls out of possession, so a Reaper must carry it at all times; it is more likely that souls are in the process of possession or haunting rather than wandering. Shiki is the current Reaper in this story, but what happens when he can't send a certain soul to the Underworld?