This trophy is titled "
Man in the Box" and it requires you to find 10 Straight Jackets scattered throughout the Lux Aeterna Psychiatric Hospital.
*** Spoiler - click to reveal ***Straight Jacket 1 - After finding the room number for Iris, dispossess the receptionist and head straight ahead into the office. The first straight jacket will be on the ground in the back right of it (Straight Jacket 1).
Straight Jacket 2 - Leave the office and hang a right up the stairs. Walk around the top toward the portal that was at the top of the left set of stairs. The second straight jacket will be on the ground a few steps from the portal (Straight Jacket 2).
Straight Jacket 3 - Help Joy advance past the first camera and she will crouch behind a door and mention there is another camera. The straight jacket is on the other side of this door waiting to be revealed (Straight Jacket 10).
Straight Jacket 4 - After disrupting the third camera for joy, walk through the wall the camera is on. In the patients room, on the floor, will be jacket four (Straight Jacket 3).
Straight Jacket 5 - Possess Joy at the portal and dispossess her as she walks passed the fifth straight jacket (Straight Jacket 7).
Straight Jacket 6 - After separating from Joy, head straight ahead through the sealed section. The sixth straight jacket will be on the floor at the back wall when the hallway turns left (Straight Jacket 6).
Straight Jacket 7 - Proceed into the old room with the two portals. Drop down into the collapsed floor and turn around. Enter the area under the floor and turn left to find the seventh straight jacket in the corner (Straight Jacket 4).
Straight Jacket 8 - Possess the cat at the collapsed floor and head through the vents. Drop down to the next level and you'll hear demons scream. Turn to the right to see the eighth straight jacket shining in a corner (Straight Jacket 9).
Straight Jacket 9 - Defeat the demons and make your way through the surgical theater that's behind the area where the portals are. Exit the theater to the right on the top floor of the observation area and teleport through the ghost barricade. Walk through the door to find the ninth straight jacket on the floor (Straight Jacket 8).
Straight Jacket 10 - After speaking with Iris, exit her room and enter the room to the left of hers, Room 217, to find the final straight jacket on the floor (Straight Jacket 5). Pick it up to unlock the trophy.
Here is the YouTube video I followed to pick up the straight jackets: