Get the "Nina's Clothes" from a closet.

Get the "Basement Key" in the kitchen.

Go to the basement using the "Basement Key."

Go ahead in front of the room with the obese man watching a porn movie.

Pass the hallway where dick-like monsters are wandering(hide in hiding spots to avoid them).

Get the "Box Cutter" in the room monster lives under floor.

Cut the dirty painting of the small room with the "Box Cutter" to get the "Fake Holy Grail."

Take the "Holy Grail" from the wall and place the "Fake Holy Grail."

Scoop water by the "Holy Grail" and defeat the monsters under the floor.

Down the ladder and get the "Music Box" on the table.

Follow the passages and return to the room where the obese man is watching a porn movie, and place the "Music Box" on the table.

Open the curtain, press the switch on the floor and get the "Control Panel Key."

Open the shutter using the "Control Panel Key."

Press the panels on the wall in the correct order .
*Answer:Lower left , lower center, upper center, upper right, lower right, upper left.

Open the unlocked door and walk down the hallway...