Rinsen Shirae holds the position of head inspector for a Kōgon Sect district, an organization dedicated to countering supernatural threats. His duties involve delivering tactical and logistical support to soldier monks battling Shikabane—reanimated corpses central to the conflict—on the front lines. This support extends beyond combat to encompass administrative tasks and ceremonial obligations.

He personally oversees funeral arrangements and burial rites for sect members who perish in service, notably conducting the ceremonies for Keisei Tagami after his demise. This responsibility underscores his role within the sect's hierarchy, ensuring proper recognition and memorialization of fallen members.

A Shakujō staff serves as his primary implement in both combat operations and ceremonial contexts, aligning with his identity as a monastic figure. His physical appearance features gray hair and distinctive blue and olive eyes. His design consistently reflects his functional portrayal as a supporting element within the Kōgon Sect's organizational structure.