Triangle Heart

Triangle Heart (とらいあんぐるハート, Toraianguru Hāto?), abbreviated as Toraha, is a series of eroge and OVAs that is most noted for its spin-off series, Magical Girl Lyrical Nanoha. The name comes from the fact that each cast focuses on a "triangle" of one boy and two girls, though there are many other heroines.

The Triangle Heart: Sweet Songs Forever (とらいあんぐるハート～Sweet Songs Forever～?) OVA, based on the game Triangle Heart 3, focuses on a boy named Kyōya Takamachi who, with his cousin-turned-sister, vows to protect a childhood friend from a mysterious terrorist organization.

There have also been two fanbox games, Love Love Toy Box, based on Triangle Heart 2, and Lyrical Toy Box, based on Triangle Heart 3.

The three games were later republished into a single DVD title on 14 June 2002.

Three manga were made for the series. Two versions of Triangle Heart 3: Sweet Songs Forever were published, one by KSS (4 volumes), and the other by SOFTBANK Publishing Inc. (1 volume). Sweet Songs Forever 4 koma KINGS was published by Studio DNA.