Here is the full list of all 38 Meltys Quest achievements.
You lost on purpose didn't you.
Wear the Nurse Uniform.
Give life twenty times.
Achieve bliss a total of 100 times or more.
Have exactly 7 in all three cream related experiences.
Pick the fourth option while talking to Zanelli.
Read Garnet's letter.
Cannonball!!
Pointless, useless, futile, meaningless.
Meet the wandering swordsman while having done the oldest profession in the game five times or more.
Wear Melty's new favorite battle outfit.
Wear only what you were born with.
Save the world.
Get the Pure Ending while in Princess Mode.
See all six endings.
Defeat the secret boss on True Princess Mode.
Defeat the final boss on True Princess Mode.
Wear the JK Clothes.
Defeat the final boss while only using Love Shot or Love Wave to do damage to the final boss.
Mine an iron ore.
Give the Red Potion to Rudolf.
Obtain the sword of a king.
Complete the rebuild of Castle Rothstein.
Defeat a chicken. Wow.
Slay a relic of the past.
Learn a Skill from using an Item.
Obtain the secret outfit.
Time to kick some butt!
Face the first boss of True Princess Mode.
Help someone prepare for their graduation.
Oh hey, didn't see you there.
Got Milk?
Defeat Dark Globbers while only using Love Shot or Love Wave to do damage.
Mano a Mano Defeat Dark Limey using only Strike skills, Guard or Items.
Defeat Dark Lilf while wearing an Apron.
Let Dark Pietra defeat herself.
View the hidden ending.
Defeat D.M.U. on True Princess mode without retreating during the fight.