Here is the full list of all 38 Meltys Quest achievements.
Have exactly 7 in all three cream related experiences.
Defeat the secret boss on True Princess Mode.
Defeat the final boss on True Princess Mode.
Pick the fourth option while talking to Zanelli.
Obtain the sword of a king.
Pointless, useless, futile, meaningless.
Meet the wandering swordsman while having done the oldest profession in the game five times or more.
Face the first boss of True Princess Mode.
Got Milk?
Oh hey, didn't see you there.
Give life twenty times.
Obtain the secret outfit.
Complete the rebuild of Castle Rothstein.
Defeat a chicken. Wow.
Wear Melty's new favorite battle outfit.
Wear only what you were born with.
Learn a Skill from using an Item.
Read Garnet's letter.
Achieve bliss a total of 100 times or more.
Help someone prepare for their graduation.
Wear the JK Clothes.
Defeat the final boss while only using Love Shot or Love Wave to do damage to the final boss.
Slay a relic of the past.
Save the world.
Time to kick some butt!
Cannonball!!
Wear the Nurse Uniform.
Mine an iron ore.
You lost on purpose didn't you.
Give the Red Potion to Rudolf.
Get the Pure Ending while in Princess Mode.
See all six endings.
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.