有馬 貴将

Arima Kishou is a Special Class Ghoul Investigator famously known as the CCG's Reaper (CCGの死神). He is a prominent figure within the organization and was widely regarded as a genius. 

He garnered an impressive list of achievements during his eighteen years as an investigator, from leading the prestigious S3 Squad to single-handedly turning the tides of large operations. His lethal battle prowess earned him many names, including the White Reaper (白い死神, Shiroi Shinigami), among others.

Tokyo Ghoul Wikia