The first Windows version of Touhou series.
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During a peaceful summer in Gensokyo, an unnatural scarlet mist appears without warning and covers much of the land. It is strong enough to block out the sun, causing the affected areas to become dark and cold. Reimu Hakurei, a shrine maiden working at the Hakurei Shrine, feels it is a shrine maiden's duty to find the cause of this unnatural weather. Marisa Kirisame, a black-clothed magician, hopes that the person casting the spell will have some interesting items to collect. Depending on who you choose, only one of these two heroines actually goes out and investigates.
