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Hoshimachi Suisei is a virtual YouTuber who is a member of hololive. Formerly part of Hololive's singers division, Inonaka Music, and an independent before that.
Hard-working, energetic and exceptionally skilled at Tetris, Suisei's odd personality lapses (especially in games where she can kill her fellow streamers) led to her nickname "Psychopath Suisei".
She also happens to be a competent illustrator, as she (the person behind the character) designed herself and her early outfits.