|Allies||Aya Drevis, Snowball|
Maria is the assistant and the lover of Alfred Drevis, living with the Drevis family in their mansion. She is a critical story character and one of the deciding factors for the ending achieved.
Maria is a young woman, with dark brown hair, shoulder-length, tied in two braids, light green eyes, and red lipstick on her lips, she wears a green and white nurse's uniform, with a pink choker on her neck.
In flashbacks, her hair was down, and she wore a white sleeveless dress, with collar V-shaped.
She is a kind-hearted woman, as seen in the flashbacks, and in the game she is very loyal to Alfred and his family, Aya and Monika Drevis. Her loyalty to those who show her kindness and continue to show her kindness knows no bounds. An example of that is when the player chooses to go with mother's wish, Maria kills Aya and makes her into a doll to "take over the duty" out of devotion.
However, once Maria is betrayed she loses her loyalty. When Alfred struck her with his chainsaw and if the player chooses to treat her injury then her loyalty shifts to Aya. That happens because Aya shows her the compassion she lost from the doctor.
Although, it doesn't seem as if she cares that she's hurting Alfred's wife when the affair is happening. Then again it could be her blind devotion to him that clouds her judgement.
Maria was once a homeless orphan girl on the street, before Alfred Drevis took her. At first, he had been hoping to have her as one of his subjects. However, upon discovering her skill at medical healing and care as she treated a dying patient of his to good health again, he could not pass up the chance to keep her as his assistant. Maria fell in love with him because he was the only one who has ever showed her any kindness and was the one that took her. This is all learned from her diary found in her room. It will also seem that Alfred also taught Maria the advanced art of lethally throwing knives, seeing as she threw knives at Dio and Alfred with deadly precision.
"Doctor, it has been a year to the day since I came to this mansion. I will never forget that day…."
"Yesterday, I encountered a young boy. He was very lovely, even moreso than the mistress. But the moment he saw me, he ran off crying. Is my face indeed so frightening…? The mistress always seems scared of me as well. I suppose it's the eyes…. Well, I'm sure it's that the mistress dislikes me. It cannot be helped… I did take away the doctor…. Surely, I could not replace her mother."
He is the lover of Maria. She seems to love him very deeply and is very loyal to him to an extent where she will do anything to please him, including killing off Aya so she could "take over the duty". This loyalty and love stems from when she was a bum on the street; he took her in, fed her, and expressed that he needed her. And in return she devoted herself to him until he betrayed her by striking her with his chainsaw, of course.
The mistress of Maria and daughter of her lover, Alfred. She cares about Aya and understands why Aya dislikes her. She is accepting of that fact. If the true ending is obtained, Aya and Maria begin to bond because they've both been betrayed by Alfred. Maria is shown to be working with Aya who is now an adult. And she seems sad that her mistress is much like her father. However, in the bad ending, Maria will knock unconscious Aya and carry out Alfred's line of work without hesitation under the pretense that "Doctor, you are with us no longer. But please, take heart... I shall take on the duty... The future you wished for the mistress... I shall see it out... So please... rest in peace... Doctor.."
If you attempt to read Maria's diary a second time, Maria mentions running into a boy like Dio who ran when she saw him. He was apparently among the first of the test subjects she sees before realizing what the doctor does.
- Maria may be a reference to Sakuya Izayoi from the Touhou Project series of games as both of them are maids, both of them serve at least one psychopath, both of them have braids in their hair and both of them throw knives in a lethal way. As of right now, this is unconfirmed and merely speculation.