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