 The light novel side story "The Spirits are Forever With You" reveals Szayelaporro was originally an alchemist in life before he and his older brother Ilfort Grantz were devoured by a Menos that manifested from the souls of those the brothers had killed.Szayelaporro retained his sense of self and became the Hollow's core as he eventually evolved in a Vasto Lorde serving under Baraggan.He offered himself to Aizen to become the first "Zero Espada" before deciding to purge Ilfort from his body to perfect himself, gradually rebuilding his strength after losing much of his power in the process.