Here is the full list of all 94 Hentai Pair achievements.
I found it!
10/10
I am the best!
Level 10
Level 9
9/10
8/10
Level 8
Level 7
7/10
Level 6
6/10
5/10
Level 5
High Five
4/10
Level 4
Level 3
3/10
2/10
Level 2
1/10
Level 1
Easy One