Kogarasumaru acts as a messenger for the Ohanamishuu, an organization fighting supernatural threats. She coordinates missions and recruits other Mitsurugi, such as persuading the reluctant Kinjiraden through a playful chase and an appeal to her sense of purpose. She leads group activities, managing strong-willed individuals like the Tenka Goken during chaotic situations.

Her personality merges formality with approachability. She employs archaic speech, calling herself "warawa" and addressing others as "o-nushi". While typically composed, she occasionally displays naivety and lacks modern common sense. She communicates with birds, especially crows, indicating a connection to nature. She enjoys swimming but dislikes hot baths.

Kogarasumaru acknowledges feelings of loneliness, relating to Kinjiraden's isolation while viewing such emotions as trials. She demonstrates patience and perceptiveness, noticing subtle distress in others and offering reassurance. Her combat abilities include an area-of-effect attack ("痕ヲ逃サズ") and an ultimate technique involving omnidirectional strikes ("斬リ乱レル羽").

In recruiting Kinjiraden, she blends playful provocation with genuine recognition of her skills, emphasizing fulfillment beyond solitude. This illustrates her commitment to uniting Mitsurugi against emerging threats, balancing duty with empathy.