Here is the full list of all 19 Demonologist achievements.
Revive your friend with a Tarot Card.
Successfully joined the "family."
Exorcise the ghost in the Bedlam
Play on the Bedlam map
Buy the Lighthouse.
Play on the Kurosawa House map
Buy the Pub.
Die once.
Play on the Hospital map
Exorcise the ghost 5 times.
Play on the Cyclone Street map.
Purchase Two Crucifix
Take Two Photos Of The Ghost.
Exorcise the ghost once.
Correctly identify the ghost 3 times.
Read EMF Level 5.
Correctly identify the ghost once.
Play on the Abandoned House map.