—There once was a manor on the hill where two witches lived.

Mahoutsukai no Yoru is a novel written by Nasu in his early 20s, and was adapted into a game 12 years later. The story and its world view has become the backbone of all other TYPE-MOON works, including Kara no Kyoukai, Tsukihime, and Fate/stay night, in other words, Mahoutsukai no Yoru is truly the origin of TYPE-MOON's fictional world—the beginning of TYPE-MOON.

The story takes place in the late 1980s, an exciting time before the advent of cellphones and the Internet. A boy from rural countryside who had just arrived in the city meets two mysterious girls—the honest and unsophisticated Shizuki Soujuurou, the outgoing modern magus Aozaki Aoko, and the reserved witch Kuonji Alice who grew up isolated from the outside world—the fate of these three people is about to cross in the mansion on top of the hill. The story of Mahoutsukai no Yoru is not one about romance, but a slice-of-life tale of three people living together not out of feelings for each other, but out of convenience and necessity.