Here is the full list of all 17 Negligee achievements. It takes around 2-3 hours to unlock all of the achievements on Windows.
Complete all endings for the Game
Unlock Sophie's Bad Ending
Unlock Jasmin's Bad Ending
Unlock Charlotte's Bad Ending
Hire Jasmin during the Interview
Hire Charlotte during the Interview
Select Jasmin for the Permanent Position
Select Charlotte for the Permanent Position
Unlock the Bonus Epilogue for Jasmin
Unlock the Bonus Epilogue for Charlotte
Pick Perfect Outfits for Yuuki & Melissa
Unlock all of the games Epilogues
Complete the games ultimate Harem ending
Get Fired from the Store
Hire Sophie during the Interview
Select Sophie for the Permanent Position
Unlock the Bonus Epilogue for Sophie