Here is the full list of all 45 AI: The Somnium Files achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.
Obtained all other trophies.
Confronted Hitomi with the evidence with no mistakes.
Confronted So with the evidence with no mistakes.
Confronted Ota with the evidence with no mistakes.
Confronted Iris with the evidence with no mistakes.
Checked absolutely everything in Boss's office.
Admired the Sagan's stereo equipment.
Discovered the marriage of the yakuza and the nurse.
Collected all the "Dream Album" files.
Found all hidden items in Somnium.
Finished the final investigation.
Kept your cool and did not shoot Saito.
Collected all the "Persons" files.
Day 6: Wednesday - Cleared Saito's Somnium.
Finished Annihilation Route investigation.
Day 5: Tuesday - Cleared Boss's Somnium.
Cleared the shooting event at the Sagan residence with no misses.
Day 5: Tuesday - Cleared Hitomi's Somnium.
Finished Iris's investigation.
Day 5: Tuesday - Cleared Iris's Somnium.
Saw This Man twice in Somnium.
Cleared the shooting event at the Warehouse District with no misses.
Day 4: Monday - Cleared Iris's Somnium.
Cleared the shooting event at Golden Yokocho with no misses.
Collected 100 "Appendix" files.
Day 3: Sunday - Cleared So's Somnium.
X-rayed the Mermaid.
Found 6 hidden items in Somnium.
Finished Ota's investigation.
Day 5: Tuesday - Cleared Mayumi's Somnium.
Had Aiba wear the basket and the pot in Somnium.
Saw three autographs of crazy customers in Somnium.
Finished Mizuki's investigation.
Day 6: Wednesday - Cleared Date's Somnium.
Almost got cursed by Adorabbit in Somnium.
Cleared the shooting event at the Sejima residence with no misses.
Asked out the receptionist to Atami.
Day 4: Monday - Cleared Ota's Somnium.
Day 4: Monday - Cleared #89's Somnium.
Day 3: Sunday - Cleared Iris's Somnium.
Cleared the shooting event at the Kumakura office with no misses.
Enjoyed a fulfilling chat with Kagami.
Day 2: Saturday - Cleared Mizuki's Somnium.
Day 1: Friday - Cleared Date's Somnium.
Found 1 hidden item in Somnium.