Touhou character. First introduced as the stage five boss in Legacy of Lunatic Kingdom. Later appeared as a prominent character in the manga Visionary Fairies in Shrine. A Hell fairy and subordinate of Hecatia Lapislazuli.
She has very long blonde hair and pink eyes, and wears a polka-dot jester cap and American flag-themed clothes: a short dress/shirt with a frilled shirt collar or neck ruff, and pantyhose/leggings/pants. As a fairy, she has plain fairy wings, and she also carries a torch with her.
She has the power to drive someone to madness.
According to ZUN, she's specifically a Lampad, a kind of underworld nymph which are companions of the Greek goddess Hecate, on whom Hecatia Lapislazuli is based.