This manga is based on the Majo no Ie - Ellen no Nikki (The Witch’s House - The Diary of Ellen) novel that author and game creator Fummy released as a prequel to the creator’s own Majo no Ie horror puzzle game. The original game casts players in the role of Viola, a girl who wakes up in the middle of a forest, where a path of roses leads her to the house of a witch named Ellen. She enters the house, and must find a way out again. The prequel novel centres on the story of how Ellen became a witch.
(Source: Anime News Network)
