Here is the full list of all 11 Negligee: Spring Clean Prelude achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Complete all routes through the Demo.
Choose the right type of Lingerie for Evie.
Choose the right type of Lingerie for Samantha.
Choose the right type of Lingerie for Rias.
Select the correct outfit for Jasmin to wear.
Select the correct outfit for Charlotte to wear.
Select the correct outfit for Karen to wear.
Select the correct outfit for Hannah to wear.
Checkout the end of game ad for the full game.
Unlock Jasmin as another character to play as.
Select the correct outfit for Sophie to wear.