In the Netherworld, Godou meets the god behind the current situation and finds out several interesting things. Meanwhile, Erica is struggling to endure the Netherworld's environment while fighting for her life. Ena of the Seishuuin family loses control of her Possession ability causing her sword, Ama no Murakumo, to fully possess and control her. Godou interrupts, but the Netherworld is still killing Erica. Her only chance may lie in the last Authority Godou has yet to master, that of the Youth. Back home, Shizuka is planning dire things for Godou after listening to (and misunderstanding) things Athena said about her relationship with Godou. Liliana and Yuri are interrupted in their rescue plans by the same scythe-wielding snake goddess that consumed Perseus.
恵那の力で生と不死の境界「幽世」に送られた護堂。彼はそこで恵那の保護者を名乗るスサノオと出会う。スサノオは、かつてはまつろわぬ神として顕現していたが、暴れ回ることに飽きて幽世に隠居したらしい。そしてスサノオは、護堂にある助言を授ける。 その一方、護堂を追って幽世に飛び込んだエリカは、恵那と死闘を演じていた。しかし天叢雲劍を憑依させた恵那に、エリカはついに敗北！ 駆けつけた護堂が戦いを止めるが、恵那はその場から逃走。そして幽世の空気に侵されたエリカは、死に瀕していた!!
