Here is the full list of all 13 Milky Way Prince – The Vampire Star achievements.
Avoid Critical Collapse
All Endings Completed
Try all the offerings at the Moonage Daydream
Save the Milky Way Prince
Find a way to distract him from his thoughts
Ask the tough questions
Find Anita
See the world through his eyes
Refuse to play his game
Keep an eye on the changes in your room
Pay attention to your companion
Wear perfume and see what happens
Shave and see what happens