H2O: Footprints in the Sand is a Japanese adult visual novel by Makura that was released on June 23, 2006 for Windows as a DVD; a version playable on the PlayStation 2 under the title H2O + followed on April 24, 2008 with adult content removed and added scenarios and graphics not seen in the original release. H2O is Makura's first game; a sequel named Root After and Another was later produced in October 2007. The gameplay in H2O follows a plot line that offers pre-determined scenarios with courses of interaction, and focuses on the appeal of the three female main characters. There are two modes of gameplay, the Blindness Effect and Normal Effect, where the former plays on the fact that the protagonist is blind, and the latter mode removes the added element of gameplay the Blindness Effect has. The story is broken into three parts: the original introduction and meeting, following by a separation and reunion, and finally ending with the protagonist choosing one of the girls and spending the rest of the game with her.

Comp Ace is a Japanese computer game and manga magazine published by Kadokawa Shoten. Comp Ace began as a special edition version of another one of Kadokawa Shoten's magazines, Comptiq. The first issue was released on March 26, 2005, and was published quarterly for the first three volumes which had cover illustrations by Itaru Hinoue of Key. Volumes four through nine were published bimonthly with cover art provided by Aoi Nishimata of Navel. Volume ten was published three months after volume nine, and from ten on the magazine was published monthly, now with new cover art by Naru Nanao, Hiro Suzuhira, and illustrators from Type-Moon and August. Starting with the August 2007 issue published on June 26, 2007, Comp Ace broke off from Comptiq and became its own magazine. Its main focus is on bishōjo games and manga that are based on said games.