Touhou Suimusou: Immaterial and Missing Power is the 7.5th installment of the Touhou Project by Team Shanghai Alice's sole member ZUN along with conjunction with Twilight Frontier. It is called "7.5" because the events chronologically take place between Perfect Cherry Blossom (TH07) and Imperishable Night (TH08). It was developed alongside Imperishable Night and released at the following Comiket 67.