Saving Desperate Girls, Starting from the House of the Dead

This is a story about saving despairing girls from the darkness and despair of various gal games and otherworldly realms. (The subject matter is niche, but you can still enjoy it even if you haven't played the games.)

Worlds: Death House, Euphoria, DDLC, Otherworld (four complete arcs), Alliance of Seven Shields. The novel is complete.