In Episode 52, Subaru repeatedly uses his ability "Return by Death" to go back to a critical moment before a fatal encounter with Sirius, the female Sin Archbishop of Wrath. Determined to prevent the impending tragedy, he initially leaves Emilia and Beatrice behind to face the threat alone. He discovers a boy named Lusbel, who is being manipulated by Sirius, whose power forces people to share their emotions and sensations, leading to widespread fear and chaos.

Subaru's attempt to stop Sirius on his own fails, forcing him to use "Return by Death" once again. Realizing he cannot handle the situation alone, he asks Reinhard, the Sword Saint, for help. Despite Reinhard's immense strength, their efforts have catastrophic consequences, as Sirius' powers affect everyone present. Subaru is forced to use "Return by Death" yet another time.

On his third attempt, Subaru confides in Beatrice and eventually Emilia about the looming threat posed by the Witch Cult and Sirius' powers. Beatrice suggests using the Shamac spell to counteract Sirius' influence. Together, they confront Sirius, but the plan fails when he directs his wrath at Emilia, insulting her and accusing her of trying to steal her husband away.

As the confrontation escalates, another Sin Archbishop appears—Regulus Corneas, the representative of Greed. He declares his intention to kidnap Emilia, claiming that she should become his wife.