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