Article: During the game, keep in mind that you don't have to help Maria. The game will continue even after you leave the Hidden Hall. Also, if you get a room key from Maria, don't use it. Carry on with your game until you reach near the end. Play the game like normal and solve the puzzle needed. After you have gone through the whole adventure and story, you will have choices to decide near end of the game.  There's no need to worry about incomplete gem collecting for this won't affect the ending of the game. Choose to save Father to get the second bad ending, which will commence shortly after. Spoilers: Aya's mother steps away from her daughter, surprised by her decision. A bright light will appear, and Aya's mother fades away. In a frame after that, they're back in the room with Aya's father close by. In this part, the truth will be revealed, showing that the doctor, Aya's father, actually cheated on her mother. Aya's mother possesses the young girl to show her the whole story, the truth about her father's experiments and how Aya's mother died. It is shown that Aya's father is conducting research about turning the human body into dolls, planning to do the research on his precious daughter to preserve her beauty. The doctor kills Aya's mother when she tries to stop him, stabbing her in the chest until she dies. After seeing what happened, Maria is in complete shock. She didn't want this to happen to her mistress but fearing being killed, she does what her father tells her. Together, they dispose of the mistress's body, and he tells Aya that her mother passed due to an illness. After the scene, make sure to save your game. This will be the part where the doctor will chase after Aya with a chainsaw, determined to kill her and turn her into a doll, just like her mother.  Aya's father will slowly come for you. Smash Z as fast as you can to break through the door and run! Don't stop. Run through the corridor. Run down to the last part of the corridor and wait for Aya's father to come closer. As soon as he stays still, pull the lever and run past him to the north. As soon as you burst into a room, you will find Maria, and a scene will commence. The doctor will finally reveal his true color. He even uses his chainsaw to attack Maria. Aya will check Maria and find that she's still alive. The game will then make you choose; the ending changes depending on the decision you make. It's expected that you die a couple of times because of the difficulty of the game.

What is a summary?
Don't help Maria. Choose to save Father. Run for your life.