The forest house is encountered by Kino and Hermes in the chapter 機械人形の話 -One-way Mission- while on the way to visit another country.
The house is three stories high, made of stone and brick, with no windows along the side facings. It resembles an apartment, making it look quite out of place in a forest. It is owned by a small family of three and their maid.
The room Kino and Hermes stay in is on the first floor. The furnishings are noted to have history, implying that it may have been salvaged from the original country.
The dining room features a framed image, covering a trap door which hides a food disposal chute for the mechanical dolls to clear their plates.
It is revealed that the house was built by the mechanical dolls to prevent their creator from regaining her memories of her original home and past. It becomes abandoned when the mechanical dolls choose to sink into the lake.