Here is the full list of all 100 Mosaique Neko Waifus 3 achievements. It takes around 2-3 hours to unlock all of the achievements on Windows.
FIRE "EARTHQUAKE" 10 TIMES
CLICK A PIECE WITH "SECRET PRESENT" 5 TIMES
SOLVE 20 PIECES USING "FLIP ALMOST SOLVED"
CLICK A PIECE WITH "SECRET PRESENT"
VIEW 100 PHOTOS
VIEW 10 PHOTOS
VIEW 1 PHOTO
SOLVE 4 PUZZLES WITH NIKO
SOLVE 3 PUZZLES WITH SEDUCED NIKO
SOLVE 1 PUZZLE WITH SEDUCED NIKO
ALL GIRLS JUMP OUT OF THEIR CLOTHES
COLLECT 37 ITEMS
COLLECT 40 ITEMS
SOLVE 35 PUZZLES
SOLVE 1 PUZZLE WITH NIKO
SOLVE 4 PUZZLES WITH COCO
COLLECT 35 ITEMS
SOLVE 30 PUZZLES
SOLVE 3 PUZZLES WITH SEDUCED COCO
UNLOCKED "SECRET PRESENT" IN SKI
SOLVE 1 PUZZLE WITH SEDUCED COCO
COLLECT 30 ITEMS
SOLVE 25 PUZZLES
SOLVE 1 PUZZLE WITH COCO
SOLVE 4 PUZZLES WITH SAYOURI
FIRE "CHOCOLATE AIRSTRIKE" 30 TIMES
SOLVE 3 PUZZLES WITH SEDUCED SAYOURI
SOLVE 20 PUZZLES
COLLECT 25 ITEMS
UNLOCKED "FLASH BOMB" IN SKILL TREE
"LOVE SPARKLE" FIRED 50 TIMES
UNLOCKED "EARTHQUAKE" IN SKILL TREE
UNLOCKED "FLIP ALMOST SOLVED" IN SKILL TREE
SOLVE 1 PUZZLE WITH SEDUCED SAYOURI
SOLVE 1000 BLOCKS
SOLVE 4 PUZZLES WITH LULI
SOLVE 900 BLOCKS
SOLVE 15 PUZZLES
SOLVE 800 BLOCKS
NEW_ACHIEVEMENT_DESC_1_25
SOLVE 1 PUZZLE WITH SEDUCED LULI
GAIN 30000 EXPERIENCE
SOLVE 700 BLOCKS
LEVEL UP TO LEVEL 30
"LOVE SPARKLE" FIRED 10 TIMES
SOLVE 600 BLOCKS
LEVEL UP TO LEVEL 25
UNLOCKED "LOVE SPARKLE" IN SKILL TREE
UNLOCKED "CHOCOLATE AIRSTRIKE" IN SKILL TREE
"FLARE" FIRED 15 TIMES
LEVELED 20 ABILITIES IN TOTAL
SOLVE 500 BLOCKS
LEVEL UP TO LEVEL 20
SOLVE 3 PUZZLES WITH SEDUCED LULI
CLICK THE PUZZLE PIECES 1500 TIMES
SOLVE 400 BLOCKS
LEVELED 15 ABILITIES IN TOTAL
GAIN 10000 EXPERIENCE
LEVEL UP TO LEVEL 15
SOLVE 10 PUZZLES
SOLVE 300 BLOCKS
CLICK THE PUZZLE PIECES 1000 TIMES
CLICK THE PUZZLE PIECES 900 TIMES
LEVELED 10 ABILITIES IN TOTAL
CLICK THE PUZZLE PIECES 800 TIMES
GAIN 5000 EXPERIENCE
NEW_ACHIEVEMENT_DESC_1_24
CLICK THE PUZZLE PIECES 700 TIMES
LEVEL UP TO LEVEL 10
SOLVE 200 BLOCKS
SOLVE 1 PUZZLE WITH LULI
CLICK THE PUZZLE PIECES 600 TIMES
UNLOCKED "FLARE" IN SKILL TREE
UNLOCKED "PEEK" IN SKILL TREE
CLICK THE PUZZLE PIECES 500 TIMES
CLICK THE PUZZLE PIECES 400 TIMES
SOLVE 5 PUZZLES
NEW_ACHIEVEMENT_DESC_1_23
GATHER 7 UNSPENT ABILITY POINTS
SOLVE 100 BLOCKS
CLICK THE PUZZLE PIECES 300 TIMES
CLICK THE PUZZLE PIECES 200 TIMES
SOLVE 50 BLOCKS
LEVELED 5 ABILITIES IN TOTAL
NEW_ACHIEVEMENT_DESC_1_22
CLICK THE PUZZLE PIECES 100 TIMES
LEVEL UP TO LEVEL 5
NEW_ACHIEVEMENT_DESC_1_21
SOLVE 2 PUZZLES
CLICK THE PUZZLE PIECES 50 TIMES
COLLECT 1 ITEM
COLLECT 2 ITEMS
SOLVE 1 PUZZLE
SOLVE 1 PUZZLE WITH SAYOURI
SOLVE 10 BLOCKS
CLICK THE PUZZLE PIECES 10 TIMES
LEVEL UP TO LEVEL 2
CLICK THE PUZZLE PIECES 1 TIME
SOLVE 1 BLOCK
HELLO THERE!