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