Brotherhood: Final Fantasy XV (Japanese: ブラザーフッド ファイナルファンタジーXV, Hepburn: Burazāfuddo: Fainaru Fantajī Fifutīn) is an original net animation series directed by Soichi Masui, produced by Akio Ofuji, written by Yuniko Ayana, and composed for by Yasuhisa Inoue and Susumi Akizuki.

Co-produced by Square Enix and A-1 Pictures, it is based on the setting and story of the 2016 video game Final Fantasy XV, which is thematically connected to the Fabula Nova Crystallis subseries.

Brotherhood is set within the events of Final Fantasy XV, and details the backstories of Noctis Lucis Caelum and his friends.

Brotherhood was made as part of a planned multimedia expansion of Final Fantasy XV without the need to develop a series of games.

As part of the peace agreements, Noctis Lucis Caelum—son of the reigning King Regis and heir to the Lucian throne—is to marry Lunafreya Nox Fleuret, former princess of Tenebrae and now hostage of Niflheim.

Noctis sets off to marry Lunafreya in the company of his loyal companions and friends: Gladiolus Amicitia, Prompto Argentum, and Ignis Scientia.

Ultimately, the budget was split between the total production costs of Final Fantasy XV and projected physical sales after the anime's release.

In XV, the complete party is available from the start, and since the backstory moments could not be fitted into the game, the anime serves as a similar means of allowing players to sympathize with them.

[21] Each episode's events also helped detail some of the characters' different social classes, with the cited example being the contrast between Prompto's small house and hard-working parents when compared to Gladiolus' more luxurious life.

[22] All episodes of Brotherhood were included as part of the Ultimate Collector's Edition of Final Fantasy XV on a Blu-ray disc.

[34] In her review of the anime's first episode, Meghan Sullivan of IGN praised the visuals and fight choreography, but felt that the story would be confusing to those not already familiar with the game.

[38] In an article summarizing Final Fantasy XV and its associated media, GamesRadar called the episodes "surprisingly well-written" and "well worth watching", noting its focus on personal stories compared to the grander narrative of Kingsglaive.

[39] In a similar article, Kotaku UK's Kim Snaith said that the anime "perfectly [sets] the scene for where Final Fantasy XV picks up".