Here is the full list of all 13 Neuronaut achievements.
Achieved by reaching the Ending 1
Achieved by reaching the Ending 2
Achieved by reaching the Ending 3
Achieved by reaching the Ending 4
Achieved by reaching the Ending 5
Achieved by reaching the Ending 6
Achieved by reaching the Ending 7
Achieved by reaching all the possible endings
Seduce Annie
Seduce Tessa
Seduce Lia
Seduce Milana
Achieved by unlocking all the CG in the Gallery