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