Shinji Hirako was the leader of the Fifth Division, sometimes called the Fifth Squad, among the Thirteen Court Guard Squads of the Soul Society before being forced to become a hollow by Sosuke Aizen. Afterward, Shinji became a member of the Vizards, a loose-knit group of Soul Reapers turned hollows.
Shinji Hirako chose Sosuke Aizen as his lieutenant to watch him, but Sosuke deceived Shinji. Shinji is often a source of levity and comedic relief in situations, both serious and otherwise. Shinji usually calls pretty girls his "first love" when first meeting them. The exception to this has always been his colleague Hiyori Sarugaki, whom Shinji frequently annoys. He claims to remain loyal to Ichigo, the main character of the series.