Here is the full list of all 25 Seduce Me the Otome achievements. It takes around 1-2 hours to unlock all of the achievements on Windows.
Preview the start of Seduce Me 2: The Demon War!
Be Eaten Alive by Diana's Pit Beast.
Impress the House Party Guests.
Obtain True Freedom.
Get Proposed to by James.
Be Baptized by Angels.
Obtain True Power.
Go To Paris with Naomi.
Witness Simon's Transformation with Diana and someone special...
Kiss Erik under the Moonlight.
Accept Sam for the Man he is.
Prove Your Love to Suzu.
Start your Adventure with Diana.
Find Harold Anderson's Magic Books.
Dodge Malix in time.
Get Shot in the head by Malix.
Share some Cake with Matthew.
Give Damien his Humanity.
Turn down sex, but keep your true love.
Get Proposed to by Andrew.
Unlock the Second Set of Bloopers!
Fight Malix Yourself.
Unlock the First Set of Bloopers!
Prologue Completed!
Rename the Main Character.