Tobirama Senju (千手扉間, Senju Tobirama)[1], the Second Hokage (二代目火影, Nidaime Hokage; Literally meaning "Second Fire Shadow") is the younger brother to Hashirama Senju, the First Hokage and Tsunade's grand uncle. Like his brother, Tobirama was a member of the Senju clan.(Wikia)