Here is the full list of all 92 Hell Girls achievements. It takes around 8-10 hours to unlock all of the achievements on Windows.
40 victories in battle
39 victories in battle
38 victories in battle
Collect 21 skill books
Fire Girl reaches Level 7
Thunder Girl reaches Level 7
37 victories in battle
36 victories in battle
35 victories in battle
Ice Girl reaches Level 7
34 victories in battle
33 victories in battle
32 victories in battle
Collect 20 skill books
31 victories in battle
Ice Girl reaches Level 6
30 victories in battle
29 victories in battle
28 victories in battle
27 victories in battle
Have 9 sets of fashion dresses
Thunder Girl reaches Level 6
26 victories in battle
25 victories in battle
24 victories in battle
Collect 19 skill books
23 victories in battle
Have 8 sets of fashion dresses
Connect 16 gems once
Connect 15 gems once
22 victories in battle
21 victories in battle
20 victories in battle
Have 7 sets of fashion dresses
Destroy 36 gems once
Destroy 37 gems once
Destroy 38 gems once
Destroy 39 gems once
Destroy 40 gems once
Fire Girl reaches Level 6
Thunder Girl reaches Level 5
Ice Girl reaches Level 5
19 victories in battle
18 victories in battle6
Fire Girl reaches Level 5
Collect 18 skill books
17 victories in battle
Collect 17 skill books
16 victories in battle
Collect 16 skill books
Ice Girl reaches Level 4
15 victories in battle
14 victories in battle
Have 6 sets of fashion dresses
Collect 15 skill books
Collect 14 skill books
13 victories in battle
Fire Girl reaches Level 4
Have 5 sets of fashion dresses
12 victories in battle
11 victories in battle
10 victories in battle
Collect 13 skill books
9 victories in battle
Thunder Girl reaches Level 4
8 victories in battle
Have 4 sets of fashion dresses
7 victories in battle
Connect 13 gems once
Connect 14 gems once
Connect 12 gems once
6 victories in battle
Thunder Girl reaches Level 3
Ice Girl reaches Level 3
Fire Girl reaches Level 3
5 victories in battle
Destroy 34 gems once
Collect 12 skill books
4 victories in battle
Connect 10 gems once
Thunder Girl reaches Level 2
3 victories in battle
Ice Girl reaches Level 2
Collect 11 skill books
2 victories in battle
Destroy 25 gems once
Destroy 30 gems once
Destroy 32 gems once
Destroy 20 gems once
Connect 8 gems once
Collect 10 skill books
Fire Girl reaches Level 2