World Break: Aria of Curse for a Holy Swordsman takes place at a school named Akane Academy, where students with special powers and known as Saviors are trained to defend against monsters called Metaphysicals, which brutally and indiscriminately attack humans. Saviors, divided into Shirogane (White Iron) and Kuroma (Black Magic), are the reincarnations of talented individuals who possess awakened memories of their past lives. Shirogane manifests weapons and martial techniques while Kuroma manifests magic for defense purposes.
The story follows the main protagonist, Moroha Haimura, who is unique in that he has awakened memories of two past lives: Flaga, a swordmaster and prince of a small country, and Shu Saura, a magician and King of the Netherworld. This gives Moroha the abilities of both a Shirogane and Kuroma. At the Academy, he meets Satsuki, a boisterous girl who is very boastful and brash and who was Sarasha, Flaga's sister, in her past life; and Shizuno, a calm and levelheaded girl, who was Shu Saura's wife. With his unique abilities, he joins the Striker Unit, Akane Academy's team of elite Saviors.
Moroha's plans for a peaceful school life go up in flames when Satsuki and Shizuno begin to vie for his attention and matters only get worse when Metaphysicals start appearing.
Seiken Tsukai no World Break started off as a light novel series written by Akamitsu Awamura and illustrated by Refeia. The first light novel volume was published on November 15, 2012, by SB Creative under their GA Bunko imprint. The series ended with its 22nd volume on June 14, 2018.
A manga adaptation of Seiken Tsukai no World Break serialized in Kadokawa Shoten's seinen manga magazine Comp Ace from June 2014. It has been collected in four tankōbon volumes.
An anime adaptation based on Seiken Tsukai no World Break was announced in February of 2014 and produced by Sotsu based on Volume 1-5 of the light novel. It was first aired January 11 through March 29, 2015, which has been licensed for streaming by Funimation and Crunchyroll. The opening song is Hi no Ito Rinne no Gemini (緋ノ糸輪廻ノ, GEMINI) which was composed by Katakura Mikiya and performed by Petit Milady (Aoi Yūki and Ayana Taketatsu), and the ending song is Magna Idea (マグナ・イデア, Maguna Idea), which was performed by Fortuna (Aoi Yūki, Ayana Taketatsu, Maaya Uchida and Yui Ogura).
The anime series has been licensed for streaming by Funimation and Crunchyroll.