Tagame was born in Kamakura on February 3, 1964 into a family distantly descended from samurai. The youngest of two brothers, Tagame was forbidden from reading manga as a child with the exception of the works of Osamu Tezuka, which his parents believed had literary merit. He became exposed to a broader array of manga by reading "shōnen" (boys' comics) stories in barber shop waiting rooms, notably the works of horror authors Kazuo Umezu and Go Nagai, whose manga often featured violent and sexual themes. He began drawing as a child, and by middle school was drawing amateur comics for his classmates and teachers. In his early teens he began drawing pornographic manga after reading novels by the Marquis de Sade and discovering the magazine "Renaissance", which re-printed material from underground BDSM manga zines; Tagame has remarked that he discovered his interest in BDSM before he realized he was gay.