You search the house and find 8 paintings. But then Slenderman knocked you out. Now you know Slendrina's secret and you can't leave the house... If you want to leave this place alive, you need to find 8 books. Good luck in Slenderina Must Die: The Cellar Room.
Use the WASD keys to walk around, mouse to look around. Left mouse button to fire, right mouse button to aim. Mouse wheel to change weapons. R to reload, F to pick up items, left shift to run, left CTRL to crouch, C to prone and space to jump.