Here is the full list of all 24 Sweet Dream Succubus - there are Nightmare Edition achievements.
Starting a new game for the first time.
Getting the delivery event.
Getting the church event
Getting the movie event.
Starting a game loop.
Skip a shower.
Getting the Jog event.
Getting the library event.
Discover her first name.
Discover her second name
Discover her full name
Getting the hotel event
Solve her identity, her kind and her goal.
Get the clinic event.
Wear a condom!
Making the shady guy talk.
Beat the game in 3 loops
Get all events
Get all 3 endings.
Get a girlfriend
Get looped by a movie.
Get the succubus master ending.
Get killed by the succubus.
Get to credits screen.