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Sleeves that are detached from the main upper garment. This is the trademark tag of Hakurei Reimu.
Detached sleeves can be used with sleeveless outfits, since the sleeveless tag only refers to the torso garment, which lacks attached sleeves.
See also
The following tags are aliased to this tag: armsleeves, detached_sleeve, and naked_sleeves (learn more).
The following tags implicate this tag: puffy_detached_sleeves and single_detached_sleeve (learn more).