東方永夜抄 ("Touhou Eiyashou") ~ Imperishable Night ("Eternal Night Vignette from the East")
Ninth game of the Touhou series, eighth of the mainstream lineup, and fourth of the Windows generation, as well as the third mainstream game in the same generation.
On the eve of the Harvest Moon Festival in Gensokyo, youkai sense that the moon has been stolen and replaced with a false one. Someone must freeze time and find the real moon to ensure a full moon on the night of the festival. To this end, a pair of a human and a youkai (4 pairs in total) go in search of the real moon, leading them to a genius pharmacist and her charge, the exiled princess of the Moon.
