Here is the full list of all 20 Harem Girl: Samantha achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Bonus Level 1 Completed
Set 6 Level 3 Completed
Set 6 Level 2 Completed
Set 6 Level 1 Completed
Set 5 Level 3 Completed
Set 5 Level 2 Completed
Set 5 Level 1 Completed
Set 4 Level 3 Completed
Set 4 Level 2 Completed
Set 4 Level 1 Completed
Set 3 Level 3 Completed
Set 3 Level 2 Completed
Set 3 Level 1 Completed
Set 2 Level 3 Completed
Set 2 Level 2 Completed
Set 2 Level 1 Completed
Set 1 Level 3 Completed
Set 1 Level 2 Completed
Set 1 Level 1 Completed
Bonus Level 2 Completed