shuusou gyoku

Shuusou Gyoku (秋霜玉, lit. "Autumn Frost Orb", also romanised as Syu-so-gyoku) is a vertical-scrolling danmaku shoot 'em up, and is the first official game in the Seihou Project by "Shunsatsu sare do?" (at time part of Amusement Makers). It was released specifically for the Windows operating system around December 2000.

https://en.touhouwiki.net/wiki/Shuusou_Gyoku

This tag implicates seihou (learn more).