Here is the full list of all 15 Touhou: Scarlet Curiosity achievements.
Bought a capsule toy at the Kourindou shop.
Have more than 300,000 coins in your possession as Remilia or Sakuya.
Saw any of the endings.
Spoke with Reimu at the Hakurei Shrine.
Defeated Mokou.
Landed a chain of 100 or more consecutive hits as Remilia or Sakuya.
Saw the true ending.
Dealt over 10,000 damage in a single hit as Remilia or Sakuya.
Raised Remilia or Sakuya's HP above 5000.
Raised Remilia or Sakuya's critical hit rate to 50% or higher.
Raised Remilia or Sakuya's item drop rate to 300% or higher.
Defeated Mokou in Bulllet Hell mode.
Defeated Patchouli in Bullet Hell mode.
Defeated Flandre in Bullet Hell mode.
Reached Lv. 99 as Remilia or Sakuya.