Here is the full list of all 14 Ballads at Midnight achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Always insult the guards
Finish the game at 100%
Stay with Lucius and remain human.
Free Lucius of his curse and become a vampire with him.
Stay with Lucius and become a bloodthirsty vampire with him.
Leave Lucius to live your best life
Don’t skip the credit
Choose to remain human and be kinky.
Free Lucius of his curse and remain human.
Skip the bard song.
Change the default name.
Insist your name is Lucius
Cuss out a vampire (use profanity as name).
Always make fun of the guards.