Hiroto Amamiya's first life quickly and tragically ended alongside his classmates'. In his second, due to a mishap on God's part, he was reborn with immense magic but also the same degree of bad luck. After enduring years of torture, this life also ended as he was gunned down by his former classmates.

While Hiroto is consumed by a lust for revenge, God hopes that he can let go and forgive, so he promises the boy that after using his third life to calm down, his fourth will be peaceful. Thrust into the world of Lamda, Hiroto is reborn as a dark elf-vampire half-breed. However, while he retains his immense magic, God has cursed this power so that it remains sealed away.

Hiroto—now named Vandalieu—is showered with love by his mother, Darcia, but tragedy rips this peaceful life away. Deciding that he doesn't need a fourth life, the infant death mage Vandalieu sets out on a journey alongside undead companions, ghouls, and other terrors of the night.