According to Hoshino, the series' main theme focuses on tragedy. Many characters such as Allen across the series suffer poor fates such as losing a loved one and being tempted to revive them by the Earl. Although this works, the people are revived as Akuma who consume the skin of their loved ones. This has led to her to state that an initial theme is that people should not be brought back to life. Although some characters like Kanda express unconditional love to Alma, their happiness is short-lived due to Alma dying shortly after this with another writer finding fitting for the series' dark narrative. Additionally, Allen's life becomes sadder across the series as he is forced to abandon the Black Order due to the Pope removing his rights as an exorcist and he is treated as Noah due to his connections with these characters. Nevertheless, Hoshino still tried to make it fun for the readers, stating that Allen will always have allies.