最终战争后的世界，人类接触到天然火焰就会自焚，只能依靠「狩火者」采集炎魔之火作为燃料维生。某天，灯子在森林遇见的狩火者灰十命丧现场。为了归还灰十遗留的狩犬与遗物，灯子搭乘半年一班的回收车前往首都。

搭乘回收车要前往首都的灯子，在车上和三名女性同房。她们都是因故要嫁到外地的新娘。另一方面，燠火家的主人油百七表示愿意收留无依无靠的煌四兄妹，但他向煌四开出一个条件。

煌四正式进入燠火家，认识了油百七的独生女绮罗，并且被带进新型雷瓶的研究室。另一方面，回收车抵达萤要出嫁的机织村，她也就此和灯子等人告别……

回收车被巨大白龙袭击而爆炸，勉强逃过一劫的只有灯子、火穗与照三。三人迷失在森林时，遇见了和森林共生的树人族。另一方面，煌四在中央书库和恩师火十重逢，并且在书库深处发现一段古老的记事。

灯子等人在森林被蜘蛛袭击，流浪的狩火者明乐出面搭救，就这么担任护卫要护送他们抵达首都。另一方面，燠火家正在举办狩火者的慰劳会，却出现了一名不速之客。

煌四跟着炉六进入森林进行夜间狩猎时，看见蜘蛛被狩火者抓住的场面，得知蜘蛛不会被天然火焰焚烧的秘密。另一方面，终于抵达首都的灯子等人，将伤重的照三送回自家疗养。

终于见到煌四的灯子，和煌四一起前去进入隔离地区，想找树人拿药治疗重伤的照三。虽然没达成目的，煌四却从树人口中得知世界的部分真相，并且在离开时遭受“忍”的袭击。

明乐向油百七说明回收车遇袭以及狩火者在海湾遇害的事件，希望油百七协助派遣回收车帮助各地的村庄。因应蜘蛛即将袭击首都，煌四主导开发的高射炮“雷击炮”进行试射，明乐也打算前往神宫通知神族。

Hinako's illness worsens, provoking a crisis at the Okibi mansion. Meanwhile, Touko joins Akira to confront the gods. New forces and unguessed truths emerge as Flickering Flame draws ever closer.

Fiends flood into the factory district ahead of the spider invasion. Despite Akira urging her to run, Touko stands her ground and joins the fight. But what toll will a real battle take on her? And can anyone stem the tide now?

Koushi struggles to load and operate the Lightning Cannon, but both the gods and the spiders have other ideas. Meanwhile, a chance encounter leads Touko to witness a startling scene.

With the fighting continuing unabated, the treefolk from the forbidden quarter are drawn to the surface, where they encounter a familiar face.

While each divine clan pursues a separate goal, visions of the Flickering Flame lead Touko and Koushi toward the palace. But who is she really, and can they trust her guidance?

While following secret tunnels toward the palace, Touko and Koushi suddenly find themselves in the middle of the dark forest. They still have a letter to deliver, but the divine clans won't make the journey easy.

Koushi finally reunites with Hinako. They set out for the palace, but their path brings them face to face with the last of the capital's treefolk. Meanwhile, Touko and Akira encounter a familiar face of their own.

Takimi confronts Koushi on the palace steps. The medically minded god insists that only his medicine can save Hinako, but Koushi refuses to let his sister suffer any more experiments. As tensions mount, Kira appears—seeming not quite herself.

Yuoshichi is on the rampage, seeking revenge against the divine clans, but with the Flickering Flame now residing within his own daughter, what lengths will he go to in order to achieve his ultimate goal?

A fallbeast suddenly descends on the divine palace, adding to the ongoing chaos. Touko instinctively knows that she must hunt it.

No tenemos una sinopsis en español. Ayúdamos a ampliar nuestra base de datos añadiendo una.