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