This is an intro thread for Kagetsu Tohya, meant for those who have not played or are playing the game to come and discuss. Please put plot points inside spoiler tags.
Title menu, cleaned by DragoZERO.
Kagetsu Tohya (歌月十夜, Kagetsu Tōya, lit. Ten Nights of the Verses and Moon) is TYPE-MOON's sequel to their earlier doujin visual novel game, Tsukihime, released in August 2001.
Kagetsu Tohya consists of "Twilight Glass Moon, Fairy Tale Princess", the long main story with many branches, and several shorter side stories that are unlocked one after another after related events in the main story have been read. Ten of these side stories are combined as "Ten Nights of Dream".
Source: TypeMoon Wiki (spoilers)