Kokoro(コ・コ・ロ…) is an adult bishōjo game released on December 4, 1998 in Japan by Aaru. The title is exactly pronounced Ko Ko Ro. Kokoro means "heart" in Japanese, and the title represents the word "heart" being broken. The game deals with incest, sexual abuse, homosexuality and murder. The first part and the latter part of the game's original video animation (OVA) adaptation were released by Alice Japan on December 21, 2001 and on June 21, 2002 respectively.