Here is the full list of all 69 Hyper-Casual Hentai achievements.
Solved all puzzles for image O
Completed 165 puzzles
Complete all puzzles
Found Hidden Sloth #5
Completed 160 puzzles
Found Hidden Sloth #20
Completed 155 puzzles
Solved all puzzles for image N
Found Hidden Sloth #17
Completed 150 puzzles
Found Hidden Sloth #18
Completed 145 puzzles
Solved all puzzles for image M
Found Hidden Sloth #12
Completed 140 puzzles
Completed 135 puzzles
Solved all puzzles for image L
Completed 130 puzzles
Found Hidden Sloth #19
Completed 125 puzzles
Found Hidden Sloth #13
Solved all puzzles for image K
Completed 120 puzzles
Found Hidden Sloth #11
Completed 115 puzzles
Solved all puzzles for image J
Completed 110 puzzles
Completed 105 puzzles
Found Hidden Sloth #15
Completed 100 puzzles
Solved all puzzles for image I
Completed 95 puzzles
Found Hidden Sloth #10
Completed 90 puzzles
Solved all puzzles for image H
Completed 85 puzzles
Completed 80 puzzles
Found Hidden Sloth #9
Solved all puzzles for image G
Completed 75 puzzles
Found Hidden Sloth #16
Completed 70 puzzles
Solved all puzzles for image F
Completed 65 puzzles
Completed 60 puzzles
Found Hidden Sloth #8
Solved all puzzles for image E
Completed 55 puzzles
Completed 50 puzzles
Found Hidden Sloth #4
Completed 45 puzzles
Solved all puzzles for image D
Found Hidden Sloth #14
Completed 40 puzzles
Completed 35 puzzles
Solved all puzzles for image C
Completed 30 puzzles
Completed 25 puzzles
Found Hidden Sloth #3
Solved all puzzles for image B
Found Hidden Sloth #6
Completed 20 puzzles
Completed 15 puzzles
Found Hidden Sloth #7
Solved all puzzles for image A
Completed 10 puzzles
Completed 5 puzzles
Found Hidden Sloth #2
Found Hidden Sloth #1