Full list of all 82 Secret Pie achievements.
The base game contains 48 achievements, and there are 2 DLC packs containing 34 achievements.
Start SecretPie Festival
DLC1 Chapter 1 clear
DLC1 Chapter 2 clear
DLC1 Chapter 3 clear
DLC1 Chapter 4 clear
DLC1 Chapter 5 clear
DLC1 Chapter 6 clear
DLC1 Chapter 7 clear
DLC1 Chapter 8 clear
Lina ♀♂♥ Chapter1 clear
Lina ♀♂♥ Chapter2 clear
Ran ♀♂♥ Chapter1 clear
Yui ♀♂♥ Chapter1 clear
Yui ♀♂♥ Chapter2 clear
Ran ♀♂♥ Chapter3 clear
Lina ♀♂♥ Chapter3
Start Hidden Room
DLC2 Chapter 1 clear
DLC2 Chapter 2 clear
DLC2 Chapter 3 clear
DLC2 Chapter 4 clear
DLC2 Chapter 5 clear
DLC2 Chapter 6 clear
DLC2 Chapter 7 clear
DLC2 Chapter 8 clear
DLC2 Chapter 9 clear
DLC2 Chapter 10 clear
Io ♀♂♥ Chapter1 clear
Io ♀♂♥ Chapter2 clear
Sia Sea ♀♂♥Chapter1 clear
Sia Sea ♀♂♥Chapter2 clear
Sia Sea ♀♂♥Chapter3 clear
Mary ♀♂♥Chapter1 clear