Sister Marie serves as a DJ within the Crown, a performance collective harnessing supernatural abilities called Links. Her striking nun-inspired aesthetic merges religious symbolism with her dynamic stage presence, creating a visual contrast between tradition and contemporary performance.

Active during Tokyo’s societal collapse triggered by a catastrophic blackout, she aided the Crown’s efforts to shield civilians from escalating violence, deploying her abilities alongside members such as Hallelujah, Akatsuki, and Guren. Her precise origins and the source of her powers remain undefined, though her collaborative role implies close coordination with the group’s core operatives.

Her personal history, motivations, and potential growth remain undisclosed, with her contributions framed primarily through her stationary role in the Crown’s operations. The narrative outlines no internal conflicts, evolving relationships, or direct engagement with external figures like Nagi, Hallelujah’s civilian acquaintance.

The juxtaposition of her ecclesiastical attire and modern musical profession underscores a thematic blend of sacred and secular elements, though this duality is not explicitly analyzed. Her impact on events extends only to her designated functions within the group, with no elaboration on broader plot influence or cross-media appearances. The character exists solely within the primary narrative as a stylistically distinct supporting figure, defined by her hybrid identity and operational role.