The Maid Sitting On Her Chair :P
The housemaid (or known in the game as the nursemaid) was the helper of the Rouche family. She was hired for the main purpose to take good care of Nicole A. Matty. However, she heard strange noises and saw apparitions in the house which made her write a note to express how she feels. She wanted to quit. At some times, she saw Nicole talking to someone who isn't there (Alrena Rouche). She knew the secret that Nicole was only adopted and the parents killed Alrena. The couple knew about this, so to avoid spreading the secret, they killed the nursemaid in the living room. She could be the woman with a crying voice heard by some neighbors as mentioned in the intro message.