Also known as: 秘封ナイトメアダイアリー_〜_Violet_Detector, 秘封ナイトメアダイアリー, Violet_Detector
Hifuu Nightmare Diary ~ Violet Detector
The Touhou Project's 16.5th game, starring Usami Sumireko in her dreams. Gameplay is in the vein of Shoot the Bullet and Double Spoiler. Was released at Comiket 94 on 10 August 2018.