One of the game's movie cutscenes is a live performance of an authentic Chinese erhu player. Erhu (二胡), a two-stringed fiddle, is a very popular musical instrument in China.
The mysterious "fox-face", who tortures Yuri in his dreams, is a reference to a popular element of Chinese and Japanese folklore mythology. Foxes were believed to have the ability of appearing as humans, and vice versa.
One of the game's central characters is Roger Bacon (1214–1294), an English scientist, philosopher, and alchemist. Some of the plot elements are very loosely based on his teachings.