Before Nanoha Takamachi headlined her own magical girl series, she was a side figure in the adult game Triangle Heart 3. Lyrical Toy Box is the music video that inspired Magical Girl Lyrical Nanoha, sung by hitomi under the name Minami Hokuto. It comes from a fan disc for that game, issued on June 29, 2001. The disc gathers plenty of extra content, including short story scenarios, one of which recasts Nanoha as a magical girl and served as the prototype for the later anime. Within the disc, Nanoha refers to the music video section as the opening of the anime.