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!
Start your Adventure with Diana.
Get Proposed to by Andrew.
Be Baptized by Angels.
Obtain True Power.
Accept Sam for the Man he is.
Impress the House Party Guests.
Rename the Main Character.
Witness Simon's Transformation with Diana and someone special...
Be Eaten Alive by Diana's Pit Beast.
Go To Paris with Naomi.
Prove Your Love to Suzu.
Dodge Malix in time.
Give Damien his Humanity.
Share some Cake with Matthew.
Kiss Erik under the Moonlight.
Get Proposed to by James.
Turn down sex, but keep your true love.
Get Shot in the head by Malix.
Obtain True Freedom.
Unlock the Second Set of Bloopers!
Fight Malix Yourself.
Find Harold Anderson's Magic Books.
Unlock the First Set of Bloopers!
Prologue Completed!