Tsumugi is an introverted and gentle honours student who becomes passionate about her favorite series and cosplay. She sees herself as plain and values making costumes over wearing them. Despite her timid nature, she's skilled at blending in and following majority decisions. She's skilled in deception, portraying herself as plain but able to control people. She can cosplay as characters very well to the point she is lost in them, but cannot cosplay real people without breaking down in rashes.