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